Author: "White, Theodore" / Search Limiters: Full Text - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"White, Theodore"' showing total 358 results

Start Over Author "White, Theodore" Search Limiters Full Text

358 results on '"White, Theodore"'

1. Observation of disorder-free localization and efficient disorder averaging on a quantum processor

Author: Gyawali, Gaurav, Cochran, Tyler, Lensky, Yuri, Rosenberg, Eliott, Karamlou, Amir H., Kechedzhi, Kostyantyn, Berndtsson, Julia, Westerhout, Tom, Asfaw, Abraham, Abanin, Dmitry, Acharya, Rajeev, Beni, Laleh Aghababaie, Andersen, Trond I., Ansmann, Markus, Arute, Frank, Arya, Kunal, Astrakhantsev, Nikita, Atalaya, Juan, Babbush, Ryan, Ballard, Brian, Bardin, Joseph C., Bengtsson, Andreas, Bilmes, Alexander, Bortoli, Gina, Bourassa, Alexandre, Bovaird, Jenna, Brill, Leon, Broughton, Michael, Browne, David A., Buchea, Brett, Buckley, Bob B., Buell, David A., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Cabrera, Anthony, Campero, Juan, Chang, Hung-Shen, Chen, Zijun, Chiaro, Ben, Claes, Jahan, Cleland, Agnetta Y., Cogan, Josh, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Das, Sayan, Debroy, Dripto M., De Lorenzo, Laura, Barba, Alexander Del Toro, Demura, Sean, Di Paolo, Agustin, Donohoe, Paul, Drozdov, Ilya, Dunsworth, Andrew, Earle, Clint, Eickbusch, Alec, Elbag, Aviv Moshe, Elzouka, Mahmoud, Erickson, Catherine, Faoro, Lara, Fatemi, Reza, Ferreira, Vinicius S., Burgos, Leslie Flores, Forati, Ebrahim, Fowler, Austin G., Foxen, Brooks, Ganjam, Suhas, Gasca, Robert, Giang, William, Gidney, Craig, Gilboa, Dar, Gosula, Raja, Dau, Alejandro Grajales, Graumann, Dietrich, Greene, Alex, Gross, Jonathan A., Habegger, Steve, Hamilton, Michael C., Hansen, Monica, Harrigan, Matthew P., Harrington, Sean D., Heslin, Stephen, Heu, Paula, Hill, Gordon, Hilton, Jeremy, Hoffmann, Markus R., Huang, Hsin-Yuan, Huff, Ashley, Huggins, William J., Ioffe, Lev B., Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Jordan, Stephen, Joshi, Chaitali, Juhas, Pavol, Kafri, Dvir, Kang, Hui, Khaire, Trupti, Khattar, Tanuj, Khezri, Mostafa, Kieferová, Mária, Kim, Seon, Klimov, Paul V., Klots, Andrey R., Kobrin, Bryce, Korotkov, Alexander N., Kostritsa, Fedor, Kreikebaum, John Mark, Kurilovich, Vladislav D., Landhuis, David, Lange-Dei, Tiano, Langley, Brandon W., Laptev, Pavel, Lau, Kim-Ming, Guevel, Loïck Le, Ledford, Justin, Lee, Joonho, Lee, Kenny, Lester, Brian J., Li, Wing Yan, Lill, Alexander T., Liu, Wayne, Livingston, William P., Locharla, Aditya, Lundahl, Daniel, Lunt, Aaron, Madhuk, Sid, Maloney, Ashley, Mandrà, Salvatore, Martin, Leigh S., Martin, Steven, Martin, Orion, Maxfield, Cameron, McClean, Jarrod R., McEwen, Matt, Meeks, Seneca, Megrant, Anthony, Mi, Xiao, Miao, Kevin C., Mieszala, Amanda, Molina, Sebastian, Montazeri, Shirin, Morvan, Alexis, Movassagh, Ramis, Neill, Charles, Nersisyan, Ani, Newman, Michael, Nguyen, Anthony, Nguyen, Murray, Ni, Chia-Hung, Niu, Murphy Yuezhen, Oliver, William D., Ottosson, Kristoffer, Pizzuto, Alex, Potter, Rebecca, Pritchard, Orion, Pryadko, Leonid P., Quintana, Chris, Reagor, Matthew J., Rhodes, David M., Roberts, Gabrielle, Rocque, Charles, Rubin, Nicholas C., Saei, Negar, Sankaragomathi, Kannan, Satzinger, Kevin J., Schurkus, Henry F., Schuster, Christopher, Shearn, Michael J., Shorter, Aaron, Shutty, Noah, Shvarts, Vladimir, Sivak, Volodymyr, Skruzny, Jindra, Small, Spencer, Smith, W. Clarke, Springer, Sofia, Sterling, George, Suchard, Jordan, Szalay, Marco, Szasz, Aaron, Sztein, Alex, Thor, Douglas, Torunbalci, M. Mert, Vaishnav, Abeer, Vdovichev, Sergey, Vidal, Guifré, Heidweiller, Catherine Vollgraff, Waltman, Steven, Wang, Shannon X., White, Theodore, Wong, Kristi, Woo, Bryan W. K., Xing, Cheng, Yao, Z. Jamie, Yeh, Ping, Ying, Bicheng, Yoo, Juhwan, Yosri, Noureldin, Young, Grayson, Zalcman, Adam, Zhang, Yaxing, Zhu, Ningfeng, Zobrist, Nicholas, Boixo, Sergio, Kelly, Julian, Lucero, Erik, Chen, Yu, Smelyanskiy, Vadim, Neven, Hartmut, Kovrizhin, Dmitry, Knolle, Johannes, Halimeh, Jad C., Aleiner, Igor, Moessner, Roderich, and Roushan, Pedram
Subjects: Quantum Physics, Condensed Matter - Disordered Systems and Neural Networks, Condensed Matter - Strongly Correlated Electrons, High Energy Physics - Lattice
Abstract: One of the most challenging problems in the computational study of localization in quantum manybody systems is to capture the effects of rare events, which requires sampling over exponentially many disorder realizations. We implement an efficient procedure on a quantum processor, leveraging quantum parallelism, to efficiently sample over all disorder realizations. We observe localization without disorder in quantum many-body dynamics in one and two dimensions: perturbations do not diffuse even though both the generator of evolution and the initial states are fully translationally invariant. The disorder strength as well as its density can be readily tuned using the initial state. Furthermore, we demonstrate the versatility of our platform by measuring Renyi entropies. Our method could also be extended to higher moments of the physical observables and disorder learning.
Published: 2024

2. Visualizing Dynamics of Charges and Strings in (2+1)D Lattice Gauge Theories

Author: Cochran, Tyler A., Jobst, Bernhard, Rosenberg, Eliott, Lensky, Yuri D., Gyawali, Gaurav, Eassa, Norhan, Will, Melissa, Abanin, Dmitry, Acharya, Rajeev, Beni, Laleh Aghababaie, Andersen, Trond I., Ansmann, Markus, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Atalaya, Juan, Babbush, Ryan, Ballard, Brian, Bardin, Joseph C., Bengtsson, Andreas, Bilmes, Alexander, Bourassa, Alexandre, Bovaird, Jenna, Broughton, Michael, Browne, David A., Buchea, Brett, Buckley, Bob B., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Cabrera, Anthony, Campero, Juan, Chang, Hung-Shen, Chen, Zijun, Chiaro, Ben, Claes, Jahan, Cleland, Agnetta Y., Cogan, Josh, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Curtin, Ben, Das, Sayan, Demura, Sean, De Lorenzo, Laura, Di Paolo, Agustin, Donohoe, Paul, Drozdov, Ilya, Dunsworth, Andrew, Eickbusch, Alec, Elbag, Aviv Moshe, Elzouka, Mahmoud, Erickson, Catherine, Ferreira, Vinicius S., Burgos, Leslie Flores, Forati, Ebrahim, Fowler, Austin G., Foxen, Brooks, Ganjam, Suhas, Gasca, Robert, Genois, Élie, Giang, William, Gilboa, Dar, Gosula, Raja, Dau, Alejandro Grajales, Graumann, Dietrich, Greene, Alex, Gross, Jonathan A., Habegger, Steve, Hansen, Monica, Harrigan, Matthew P., Harrington, Sean D., Heu, Paula, Higgott, Oscar, Hilton, Jeremy, Huang, Hsin-Yuan, Huff, Ashley, Huggins, William J., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Joshi, Chaitali, Juhas, Pavol, Kafri, Dvir, Kang, Hui, Karamlou, Amir H., Kechedzhi, Kostyantyn, Khaire, Trupti, Khattar, Tanuj, Khezri, Mostafa, Kim, Seon, Klimov, Paul V., Kobrin, Bryce, Korotkov, Alexander N., Kostritsa, Fedor, Kreikebaum, John Mark, Kurilovich, Vladislav D., Landhuis, David, Lange-Dei, Tiano, Langley, Brandon W., Lau, Kim-Ming, Ledford, Justin, Lee, Kenny, Lester, Brian J., Guevel, Loïck Le, Li, Wing Yan, Lill, Alexander T., Livingston, William P., Locharla, Aditya, Lundahl, Daniel, Lunt, Aaron, Madhuk, Sid, Maloney, Ashley, Mandrà, Salvatore, Martin, Leigh S., Martin, Orion, Maxfield, Cameron, McClean, Jarrod R., McEwen, Matt, Meeks, Seneca, Megrant, Anthony, Miao, Kevin C., Molavi, Reza, Molina, Sebastian, Montazeri, Shirin, Movassagh, Ramis, Neill, Charles, Newman, Michael, Nguyen, Anthony, Nguyen, Murray, Ni, Chia-Hung, Niu, Murphy Yuezhen, Oliver, William D., Ottosson, Kristoffer, Pizzuto, Alex, Potter, Rebecca, Pritchard, Orion, Quintana, Chris, Ramachandran, Ganesh, Reagor, Matthew J., Rhodes, David M., Roberts, Gabrielle, Sankaragomathi, Kannan, Satzinger, Kevin J., Schurkus, Henry F., Shearn, Michael J., Shorter, Aaron, Shutty, Noah, Shvarts, Vladimir, Sivak, Volodymyr, Small, Spencer, Smith, W. Clarke, Springer, Sofia, Sterling, George, Suchard, Jordan, Szasz, Aaron, Sztein, Alex, Thor, Douglas, Torunbalci, M. Mert, Vaishnav, Abeer, Vargas, Justin, Vdovichev, Sergey, Vidal, Guifre, Heidweiller, Catherine Vollgraff, Waltman, Steven, Wang, Shannon X., Ware, Brayden, White, Theodore, Wong, Kristi, Woo, Bryan W. K., Xing, Cheng, Yao, Z. Jamie, Yeh, Ping, Ying, Bicheng, Yoo, Juhwan, Yosri, Noureldin, Young, Grayson, Zalcman, Adam, Zhang, Yaxing, Zhu, Ningfeng, Zobris, Nicholas, Boixo, Sergio, Kelly, Julian, Lucero, Erik, Chen, Yu, Smelyanskiy, Vadim, Neven, Hartmut, Gammon-Smith, Adam, Pollmann, Frank, Knap, Michael, and Roushan, Pedram
Subjects: Quantum Physics, Condensed Matter - Strongly Correlated Electrons, High Energy Physics - Lattice
Abstract: Lattice gauge theories (LGTs) can be employed to understand a wide range of phenomena, from elementary particle scattering in high-energy physics to effective descriptions of many-body interactions in materials. Studying dynamical properties of emergent phases can be challenging as it requires solving many-body problems that are generally beyond perturbative limits. We investigate the dynamics of local excitations in a $\mathbb{Z}_2$ LGT using a two-dimensional lattice of superconducting qubits. We first construct a simple variational circuit which prepares low-energy states that have a large overlap with the ground state; then we create particles with local gates and simulate their quantum dynamics via a discretized time evolution. As the effective magnetic field is increased, our measurements show signatures of transitioning from deconfined to confined dynamics. For confined excitations, the magnetic field induces a tension in the string connecting them. Our method allows us to experimentally image string dynamics in a (2+1)D LGT from which we uncover two distinct regimes inside the confining phase: for weak confinement the string fluctuates strongly in the transverse direction, while for strong confinement transverse fluctuations are effectively frozen. In addition, we demonstrate a resonance condition at which dynamical string breaking is facilitated. Our LGT implementation on a quantum processor presents a novel set of techniques for investigating emergent particle and string dynamics.
Published: 2024

3. Quantum error correction below the surface code threshold

Author: Acharya, Rajeev, Aghababaie-Beni, Laleh, Aleiner, Igor, Andersen, Trond I., Ansmann, Markus, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Astrakhantsev, Nikita, Atalaya, Juan, Babbush, Ryan, Bacon, Dave, Ballard, Brian, Bardin, Joseph C., Bausch, Johannes, Bengtsson, Andreas, Bilmes, Alexander, Blackwell, Sam, Boixo, Sergio, Bortoli, Gina, Bourassa, Alexandre, Bovaird, Jenna, Brill, Leon, Broughton, Michael, Browne, David A., Buchea, Brett, Buckley, Bob B., Buell, David A., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Cabrera, Anthony, Campero, Juan, Chang, Hung-Shen, Chen, Yu, Chen, Zijun, Chiaro, Ben, Chik, Desmond, Chou, Charina, Claes, Jahan, Cleland, Agnetta Y., Cogan, Josh, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Curtin, Ben, Das, Sayan, Davies, Alex, De Lorenzo, Laura, Debroy, Dripto M., Demura, Sean, Devoret, Michel, Di Paolo, Agustin, Donohoe, Paul, Drozdov, Ilya, Dunsworth, Andrew, Earle, Clint, Edlich, Thomas, Eickbusch, Alec, Elbag, Aviv Moshe, Elzouka, Mahmoud, Erickson, Catherine, Faoro, Lara, Farhi, Edward, Ferreira, Vinicius S., Burgos, Leslie Flores, Forati, Ebrahim, Fowler, Austin G., Foxen, Brooks, Ganjam, Suhas, Garcia, Gonzalo, Gasca, Robert, Genois, Élie, Giang, William, Gidney, Craig, Gilboa, Dar, Gosula, Raja, Dau, Alejandro Grajales, Graumann, Dietrich, Greene, Alex, Gross, Jonathan A., Habegger, Steve, Hall, John, Hamilton, Michael C., Hansen, Monica, Harrigan, Matthew P., Harrington, Sean D., Heras, Francisco J. H., Heslin, Stephen, Heu, Paula, Higgott, Oscar, Hill, Gordon, Hilton, Jeremy, Holland, George, Hong, Sabrina, Huang, Hsin-Yuan, Huff, Ashley, Huggins, William J., Ioffe, Lev B., Isakov, Sergei V., Iveland, Justin, Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Jordan, Stephen, Joshi, Chaitali, Juhas, Pavol, Kafri, Dvir, Kang, Hui, Karamlou, Amir H., Kechedzhi, Kostyantyn, Kelly, Julian, Khaire, Trupti, Khattar, Tanuj, Khezri, Mostafa, Kim, Seon, Klimov, Paul V., Klots, Andrey R., Kobrin, Bryce, Kohli, Pushmeet, Korotkov, Alexander N., Kostritsa, Fedor, Kothari, Robin, Kozlovskii, Borislav, Kreikebaum, John Mark, Kurilovich, Vladislav D., Lacroix, Nathan, Landhuis, David, Lange-Dei, Tiano, Langley, Brandon W., Laptev, Pavel, Lau, Kim-Ming, Guevel, Loïck Le, Ledford, Justin, Lee, Kenny, Lensky, Yuri D., Leon, Shannon, Lester, Brian J., Li, Wing Yan, Li, Yin, Lill, Alexander T., Liu, Wayne, Livingston, William P., Locharla, Aditya, Lucero, Erik, Lundahl, Daniel, Lunt, Aaron, Madhuk, Sid, Malone, Fionn D., Maloney, Ashley, Mandrá, Salvatore, Martin, Leigh S., Martin, Steven, Martin, Orion, Maxfield, Cameron, McClean, Jarrod R., McEwen, Matt, Meeks, Seneca, Megrant, Anthony, Mi, Xiao, Miao, Kevin C., Mieszala, Amanda, Molavi, Reza, Molina, Sebastian, Montazeri, Shirin, Morvan, Alexis, Movassagh, Ramis, Mruczkiewicz, Wojciech, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Nersisyan, Ani, Neven, Hartmut, Newman, Michael, Ng, Jiun How, Nguyen, Anthony, Nguyen, Murray, Ni, Chia-Hung, O'Brien, Thomas E., Oliver, William D., Opremcak, Alex, Ottosson, Kristoffer, Petukhov, Andre, Pizzuto, Alex, Platt, John, Potter, Rebecca, Pritchard, Orion, Pryadko, Leonid P., Quintana, Chris, Ramachandran, Ganesh, Reagor, Matthew J., Rhodes, David M., Roberts, Gabrielle, Rosenberg, Eliott, Rosenfeld, Emma, Roushan, Pedram, Rubin, Nicholas C., Saei, Negar, Sank, Daniel, Sankaragomathi, Kannan, Satzinger, Kevin J., Schurkus, Henry F., Schuster, Christopher, Senior, Andrew W., Shearn, Michael J., Shorter, Aaron, Shutty, Noah, Shvarts, Vladimir, Singh, Shraddha, Sivak, Volodymyr, Skruzny, Jindra, Small, Spencer, Smelyanskiy, Vadim, Smith, W. Clarke, Somma, Rolando D., Springer, Sofia, Sterling, George, Strain, Doug, Suchard, Jordan, Szasz, Aaron, Sztein, Alex, Thor, Douglas, Torres, Alfredo, Torunbalci, M. Mert, Vaishnav, Abeer, Vargas, Justin, Vdovichev, Sergey, Vidal, Guifre, Villalonga, Benjamin, Heidweiller, Catherine Vollgraff, Waltman, Steven, Wang, Shannon X., Ware, Brayden, Weber, Kate, White, Theodore, Wong, Kristi, Woo, Bryan W. K., Xing, Cheng, Yao, Z. Jamie, Yeh, Ping, Ying, Bicheng, Yoo, Juhwan, Yosri, Noureldin, Young, Grayson, Zalcman, Adam, Zhang, Yaxing, Zhu, Ningfeng, and Zobrist, Nicholas
Subjects: Quantum Physics
Abstract: Quantum error correction provides a path to reach practical quantum computing by combining multiple physical qubits into a logical qubit, where the logical error rate is suppressed exponentially as more qubits are added. However, this exponential suppression only occurs if the physical error rate is below a critical threshold. In this work, we present two surface code memories operating below this threshold: a distance-7 code and a distance-5 code integrated with a real-time decoder. The logical error rate of our larger quantum memory is suppressed by a factor of $\Lambda$ = 2.14 $\pm$ 0.02 when increasing the code distance by two, culminating in a 101-qubit distance-7 code with 0.143% $\pm$ 0.003% error per cycle of error correction. This logical memory is also beyond break-even, exceeding its best physical qubit's lifetime by a factor of 2.4 $\pm$ 0.3. We maintain below-threshold performance when decoding in real time, achieving an average decoder latency of 63 $\mu$s at distance-5 up to a million cycles, with a cycle time of 1.1 $\mu$s. To probe the limits of our error-correction performance, we run repetition codes up to distance-29 and find that logical performance is limited by rare correlated error events occurring approximately once every hour, or 3 $\times$ 10$^9$ cycles. Our results present device performance that, if scaled, could realize the operational requirements of large scale fault-tolerant quantum algorithms., Comment: 10 pages, 4 figures, Supplementary Information
Published: 2024

4. Thermalization and Criticality on an Analog-Digital Quantum Simulator

Author: Andersen, Trond I., Astrakhantsev, Nikita, Karamlou, Amir H., Berndtsson, Julia, Motruk, Johannes, Szasz, Aaron, Gross, Jonathan A., Schuckert, Alexander, Westerhout, Tom, Zhang, Yaxing, Forati, Ebrahim, Rossi, Dario, Kobrin, Bryce, Di Paolo, Agustin, Klots, Andrey R., Drozdov, Ilya, Kurilovich, Vladislav D., Petukhov, Andre, Ioffe, Lev B., Elben, Andreas, Rath, Aniket, Vitale, Vittorio, Vermersch, Benoit, Acharya, Rajeev, Beni, Laleh Aghababaie, Anderson, Kyle, Ansmann, Markus, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Atalaya, Juan, Ballard, Brian, Bardin, Joseph C., Bengtsson, Andreas, Bilmes, Alexander, Bortoli, Gina, Bourassa, Alexandre, Bovaird, Jenna, Brill, Leon, Broughton, Michael, Browne, David A., Buchea, Brett, Buckley, Bob B., Buell, David A., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Cabrera, Anthony, Campero, Juan, Chang, Hung-Shen, Chen, Zijun, Chiaro, Ben, Claes, Jahan, Cleland, Agnetta Y., Cogan, Josh, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Das, Sayan, Debroy, Dripto M., De Lorenzo, Laura, Barba, Alexander Del Toro, Demura, Sean, Donohoe, Paul, Dunsworth, Andrew, Earle, Clint, Eickbusch, Alec, Elbag, Aviv Moshe, Elzouka, Mahmoud, Erickson, Catherine, Faoro, Lara, Fatemi, Reza, Ferreira, Vinicius S., Burgos, Leslie Flores, Fowler, Austin G., Foxen, Brooks, Ganjam, Suhas, Gasca, Robert, Giang, William, Gidney, Craig, Gilboa, Dar, Giustina, Marissa, Gosula, Raja, Dau, Alejandro Grajales, Graumann, Dietrich, Greene, Alex, Habegger, Steve, Hamilton, Michael C., Hansen, Monica, Harrigan, Matthew P., Harrington, Sean D., Heslin, Stephen, Heu, Paula, Hill, Gordon, Hoffmann, Markus R., Huang, Hsin-Yuan, Huang, Trent, Huff, Ashley, Huggins, William J., Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Jordan, Stephen, Joshi, Chaitali, Juhas, Pavol, Kafri, Dvir, Kang, Hui, Kechedzhi, Kostyantyn, Khaire, Trupti, Khattar, Tanuj, Khezri, Mostafa, Kieferová, Mária, Kim, Seon, Kitaev, Alexei, Klimov, Paul V., Korotkov, Alexander N., Kostritsa, Fedor, Kreikebaum, John Mark, Landhuis, David, Langley, Brandon W., Laptev, Pavel, Lau, Kim-Ming, Guevel, Loïck Le, Ledford, Justin, Lee, Joonho, Lee, Kenny, Lensky, Yuri D., Lester, Brian J., Li, Wing Yan, Lill, Alexander T., Liu, Wayne, Livingston, William P., Locharla, Aditya, Lundahl, Daniel, Lunt, Aaron, Madhuk, Sid, Maloney, Ashley, Mandrà, Salvatore, Martin, Leigh S., Martin, Orion, Martin, Steven, Maxfield, Cameron, McClean, Jarrod R., McEwen, Matt, Meeks, Seneca, Miao, Kevin C., Mieszala, Amanda, Molina, Sebastian, Montazeri, Shirin, Morvan, Alexis, Movassagh, Ramis, Neill, Charles, Nersisyan, Ani, Newman, Michael, Nguyen, Anthony, Nguyen, Murray, Ni, Chia-Hung, Niu, Murphy Yuezhen, Oliver, William D., Ottosson, Kristoffer, Pizzuto, Alex, Potter, Rebecca, Pritchard, Orion, Pryadko, Leonid P., Quintana, Chris, Reagor, Matthew J., Rhodes, David M., Roberts, Gabrielle, Rocque, Charles, Rosenberg, Eliott, Rubin, Nicholas C., Saei, Negar, Sankaragomathi, Kannan, Satzinger, Kevin J., Schurkus, Henry F., Schuster, Christopher, Shearn, Michael J., Shorter, Aaron, Shutty, Noah, Shvarts, Vladimir, Sivak, Volodymyr, Skruzny, Jindra, Small, Spencer, Smith, W. Clarke, Springer, Sofia, Sterling, George, Suchard, Jordan, Szalay, Marco, Sztein, Alex, Thor, Douglas, Torres, Alfredo, Torunbalci, M. Mert, Vaishnav, Abeer, Vdovichev, Sergey, Villalonga, Benjamin, Heidweiller, Catherine Vollgraff, Waltman, Steven, Wang, Shannon X., White, Theodore, Wong, Kristi, Woo, Bryan W., Xing, Cheng, Yao, Z. Jamie, Yeh, Ping, Ying, Bicheng, Yoo, Juhwan, Yosri, Noureldin, Young, Grayson, Zalcman, Adam, Zhu, Ningfeng, Zobrist, Nicholas, Neven, Hartmut, Babbush, Ryan, Boixo, Sergio, Hilton, Jeremy, Lucero, Erik, Megrant, Anthony, Kelly, Julian, Chen, Yu, Smelyanskiy, Vadim, Vidal, Guifre, Roushan, Pedram, Lauchli, Andreas M., Abanin, Dmitry A., and Mi, Xiao
Subjects: Quantum Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Strongly Correlated Electrons
Abstract: Understanding how interacting particles approach thermal equilibrium is a major challenge of quantum simulators. Unlocking the full potential of such systems toward this goal requires flexible initial state preparation, precise time evolution, and extensive probes for final state characterization. We present a quantum simulator comprising 69 superconducting qubits which supports both universal quantum gates and high-fidelity analog evolution, with performance beyond the reach of classical simulation in cross-entropy benchmarking experiments. Emulating a two-dimensional (2D) XY quantum magnet, we leverage a wide range of measurement techniques to study quantum states after ramps from an antiferromagnetic initial state. We observe signatures of the classical Kosterlitz-Thouless phase transition, as well as strong deviations from Kibble-Zurek scaling predictions attributed to the interplay between quantum and classical coarsening of the correlated domains. This interpretation is corroborated by injecting variable energy density into the initial state, which enables studying the effects of the eigenstate thermalization hypothesis (ETH) in targeted parts of the eigenspectrum. Finally, we digitally prepare the system in pairwise-entangled dimer states and image the transport of energy and vorticity during thermalization. These results establish the efficacy of superconducting analog-digital quantum processors for preparing states across many-body spectra and unveiling their thermalization dynamics.
Published: 2024

5. Dynamics of magnetization at infinite temperature in a Heisenberg spin chain

Author: Rosenberg, Eliott, Andersen, Trond, Samajdar, Rhine, Petukhov, Andre, Hoke, Jesse, Abanin, Dmitry, Bengtsson, Andreas, Drozdov, Ilya, Erickson, Catherine, Klimov, Paul, Mi, Xiao, Morvan, Alexis, Neeley, Matthew, Neill, Charles, Acharya, Rajeev, Allen, Richard, Anderson, Kyle, Ansmann, Markus, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Atalaya, Juan, Bardin, Joseph, Bilmes, A., Bortoli, Gina, Bourassa, Alexandre, Bovaird, Jenna, Brill, Leon, Broughton, Michael, Buckley, Bob B., Buell, David, Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Campero, Juan, Chang, Hung-Shen, Chen, Zijun, Chiaro, Benjamin, Chik, Desmond, Cogan, Josh, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander, Curtin, Ben, Debroy, Dripto, Barba, Alexander Del Toro, Demura, Sean, Di Paolo, Agustin, Dunsworth, Andrew, Earle, Clint, Farhi, E., Fatemi, Reza, Ferreira, Vinicius, Flores, Leslie, Forati, Ebrahim, Fowler, Austin, Foxen, Brooks, Garcia, Gonzalo, Genois, Élie, Giang, William, Gidney, Craig, Gilboa, Dar, Giustina, Marissa, Gosula, Raja, Dau, Alejandro Grajales, Gross, Jonathan, Habegger, Steve, Hamilton, Michael, Hansen, Monica, Harrigan, Matthew, Harrington, Sean, Heu, Paula, Hill, Gordon, Hoffmann, Markus, Hong, Sabrina, Huang, Trent, Huff, Ashley, Huggins, William, Ioffe, Lev, Isakov, Sergei, Iveland, Justin, Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Juhas, Pavol, Kafri, D., Khattar, Tanuj, Khezri, Mostafa, Kieferová, Mária, Kim, Seon, Kitaev, Alexei, Klots, Andrey, Korotkov, Alexander, Kostritsa, Fedor, Kreikebaum, John Mark, Landhuis, David, Laptev, Pavel, Lau, Kim Ming, Laws, Lily, Lee, Joonho, Lee, Kenneth, Lensky, Yuri, Lester, Brian, Lill, Alexander, Liu, Wayne, Livingston, William P., Locharla, A., Mandrà, Salvatore, Martin, Orion, Martin, Steven, McClean, Jarrod, McEwen, Matthew, Meeks, Seneca, Miao, Kevin, Mieszala, Amanda, Montazeri, Shirin, Movassagh, Ramis, Mruczkiewicz, Wojciech, Nersisyan, Ani, Newman, Michael, Ng, Jiun How, Nguyen, Anthony, Nguyen, Murray, Niu, M., O'Brien, Thomas, Omonije, Seun, Opremcak, Alex, Potter, Rebecca, Pryadko, Leonid, Quintana, Chris, Rhodes, David, Rocque, Charles, Rubin, N., Saei, Negar, Sank, Daniel, Sankaragomathi, Kannan, Satzinger, Kevin, Schurkus, Henry, Schuster, Christopher, Shearn, Michael, Shorter, Aaron, Shutty, Noah, Shvarts, Vladimir, Sivak, Volodymyr, Skruzny, Jindra, Smith, Clarke, Somma, Rolando, Sterling, George, Strain, Doug, Szalay, Marco, Thor, Douglas, Torres, Alfredo, Vidal, Guifre, Villalonga, Benjamin, Heidweiller, Catherine Vollgraff, White, Theodore, Woo, Bryan, Xing, Cheng, Yao, Jamie, Yeh, Ping, Yoo, Juhwan, Young, Grayson, Zalcman, Adam, Zhang, Yaxing, Zhu, Ningfeng, Zobrist, Nicholas, Neven, Hartmut, Babbush, Ryan, Bacon, Dave, Boixo, Sergio, Hilton, Jeremy, Lucero, Erik, Megrant, Anthony, Kelly, Julian, Chen, Yu, Smelyanskiy, Vadim, Khemani, Vedika, Gopalakrishnan, Sarang, Prosen, Tomaž, and Roushan, Pedram
Subjects: Quantum Physics
Abstract: Understanding universal aspects of quantum dynamics is an unresolved problem in statistical mechanics. In particular, the spin dynamics of the 1D Heisenberg model were conjectured to belong to the Kardar-Parisi-Zhang (KPZ) universality class based on the scaling of the infinite-temperature spin-spin correlation function. In a chain of 46 superconducting qubits, we study the probability distribution, $P(\mathcal{M})$, of the magnetization transferred across the chain's center. The first two moments of $P(\mathcal{M})$ show superdiffusive behavior, a hallmark of KPZ universality. However, the third and fourth moments rule out the KPZ conjecture and allow for evaluating other theories. Our results highlight the importance of studying higher moments in determining dynamic universality classes and provide key insights into universal behavior in quantum systems.
Published: 2023
Full Text: View/download PDF

6. Josephson parametric amplifier with Chebyshev gain profile and high saturation

Author: Kaufman, Ryan, White, Theodore, Dykman, Mark I., Iorio, Andrea, Stirling, George, Hong, Sabrina, Opremcak, Alex, Bengtsson, Andreas, Faoro, Lara, Bardin, Joseph C., Burger, Tim, Gasca, Robert, and Naaman, Ofer
Subjects: Quantum Physics, Physics - Applied Physics
Abstract: We demonstrate a Josephson parametric amplifier design with a band-pass impedance matching network based on a third-order Chebyshev prototype. We measured eight amplifiers operating at 4.6 GHz that exhibit gains of 20 dB with less than 1 dB gain ripple and up to 500 MHz bandwidth. The amplifiers further achieve high output saturation powers around -73 dBm based on the use of rf-SQUID arrays as their nonlinear element. We characterize the system readout efficiency and its signal-to-noise ratio near saturation using a Sycamore processor, finding the data consistent with near quantum limited noise performance of the amplifiers. In addition, we measure the amplifiers' intermodulation distortion in two-tone experiments as a function of input power and inter-tone detuning, and observe excess distortion at small detuning with a pronounced dip as a function of signal power, which we interpret in terms of power-dependent dielectric losses., Comment: 14 pages, 10 figures
Published: 2023

7. Josephson parametric circulator with same-frequency signal ports, 200 MHz bandwidth, and high dynamic range

Author: Kwende, Randy, White, Theodore, and Naaman, Ofer
Subjects: Quantum Physics, Physics - Applied Physics
Abstract: We demonstrate a 3-port Josephson parametric circulator, matched to 50 Ohm using second order Chebyshev networks. The device notably operates with two of its signal ports at the same frequency and uses only two out-of-phase pumps at a single frequency. As a consequence, when operated as an isolator it does not require phase coherence between the pumps and the signal, thus simplifying the requirements for its integration into standard dispersive qubit readout setups. The device utilizes parametric couplers based on a balanced bridge of rf-SQUID arrays, which offer purely parametric coupling and high dynamic range. We characterize the device by measuring its full 3x3 S-matrix as a function of frequency and the relative phase between the two pumps. We find up to 15 dB nonreciprocity over a 200 MHz signal band, port match better than 10 dB, low insertion loss of 0.6 dB, and saturation power exceeding -80 dBm., Comment: 5 pages, 4 figures
Published: 2023
Full Text: View/download PDF

8. Measurement-Induced State Transitions in a Superconducting Qubit: Within the Rotating Wave Approximation

Author: Khezri, Mostafa, Opremcak, Alex, Chen, Zijun, Miao, Kevin C., McEwen, Matt, Bengtsson, Andreas, White, Theodore, Naaman, Ofer, Sank, Daniel, Korotkov, Alexander N., Chen, Yu, and Smelyanskiy, Vadim
Subjects: Quantum Physics
Abstract: Superconducting qubits typically use a dispersive readout scheme, where a resonator is coupled to a qubit such that its frequency is qubit-state dependent. Measurement is performed by driving the resonator, where the transmitted resonator field yields information about the resonator frequency and thus the qubit state. Ideally, we could use arbitrarily strong resonator drives to achieve a target signal-to-noise ratio in the shortest possible time. However, experiments have shown that when the average resonator photon number exceeds a certain threshold, the qubit is excited out of its computational subspace in a process we refer to as a measurement-induced state transition (MIST). These transitions degrade readout fidelity, and constitute leakage which precludes further operation of the qubit in, for example, error correction. Here we study these transitions experimentally with a transmon qubit by measuring their dependence on qubit frequency, average resonator photon number, and qubit state, in the regime where the resonator frequency is lower than the qubit frequency. We observe signatures of resonant transitions between levels in the coupled qubit-resonator system that exhibit noisy behavior when measured repeatedly in time. We provide a semi-classical model of these transitions based on the rotating wave approximation and use it to predict the onset of state transitions in our experiments. Our results suggest the transmon is excited to levels near the top of its cosine potential following a state transition, where the charge dispersion of higher transmon levels explains the observed noisy behavior of state transitions. Moreover, we show that occupation in these higher energy levels poses a major challenge for fast qubit reset., Comment: published version
Published: 2022
Full Text: View/download PDF

9. Overcoming leakage in scalable quantum error correction

Author: Miao, Kevin C., McEwen, Matt, Atalaya, Juan, Kafri, Dvir, Pryadko, Leonid P., Bengtsson, Andreas, Opremcak, Alex, Satzinger, Kevin J., Chen, Zijun, Klimov, Paul V., Quintana, Chris, Acharya, Rajeev, Anderson, Kyle, Ansmann, Markus, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Bardin, Joseph C., Bourassa, Alexandre, Bovaird, Jenna, Brill, Leon, Buckley, Bob B., Buell, David A., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Campero, Juan, Chiaro, Ben, Collins, Roberto, Conner, Paul, Crook, Alexander L., Curtin, Ben, Debroy, Dripto M., Demura, Sean, Dunsworth, Andrew, Erickson, Catherine, Fatemi, Reza, Ferreira, Vinicius S., Burgos, Leslie Flores, Forati, Ebrahim, Fowler, Austin G., Foxen, Brooks, Garcia, Gonzalo, Giang, William, Gidney, Craig, Giustina, Marissa, Gosula, Raja, Dau, Alejandro Grajales, Gross, Jonathan A., Hamilton, Michael C., Harrington, Sean D., Heu, Paula, Hilton, Jeremy, Hoffmann, Markus R., Hong, Sabrina, Huang, Trent, Huff, Ashley, Iveland, Justin, Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Kelly, Julian, Kim, Seon, Kostritsa, Fedor, Kreikebaum, John Mark, Landhuis, David, Laptev, Pavel, Laws, Lily, Lee, Kenny, Lester, Brian J., Lill, Alexander T., Liu, Wayne, Locharla, Aditya, Lucero, Erik, Martin, Steven, Megrant, Anthony, Mi, Xiao, Montazeri, Shirin, Morvan, Alexis, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Nersisyan, Ani, Newman, Michael, Ng, Jiun How, Nguyen, Anthony, Nguyen, Murray, Potter, Rebecca, Rocque, Charles, Roushan, Pedram, Sankaragomathi, Kannan, Schuster, Christopher, Shearn, Michael J., Shorter, Aaron, Shutty, Noah, Shvarts, Vladimir, Skruzny, Jindra, Smith, W. Clarke, Sterling, George, Szalay, Marco, Thor, Douglas, Torres, Alfredo, White, Theodore, Woo, Bryan W. K., Yao, Z. Jamie, Yeh, Ping, Yoo, Juhwan, Young, Grayson, Zalcman, Adam, Zhu, Ningfeng, Zobrist, Nicholas, Neven, Hartmut, Smelyanskiy, Vadim, Petukhov, Andre, Korotkov, Alexander N., Sank, Daniel, and Chen, Yu
Subjects: Quantum Physics
Abstract: Leakage of quantum information out of computational states into higher energy states represents a major challenge in the pursuit of quantum error correction (QEC). In a QEC circuit, leakage builds over time and spreads through multi-qubit interactions. This leads to correlated errors that degrade the exponential suppression of logical error with scale, challenging the feasibility of QEC as a path towards fault-tolerant quantum computation. Here, we demonstrate the execution of a distance-3 surface code and distance-21 bit-flip code on a Sycamore quantum processor where leakage is removed from all qubits in each cycle. This shortens the lifetime of leakage and curtails its ability to spread and induce correlated errors. We report a ten-fold reduction in steady-state leakage population on the data qubits encoding the logical state and an average leakage population of less than $1 \times 10^{-3}$ throughout the entire device. The leakage removal process itself efficiently returns leakage population back to the computational basis, and adding it to a code circuit prevents leakage from inducing correlated error across cycles, restoring a fundamental assumption of QEC. With this demonstration that leakage can be contained, we resolve a key challenge for practical QEC at scale., Comment: Main text: 7 pages, 5 figures
Published: 2022
Full Text: View/download PDF

10. Non-Abelian braiding of graph vertices in a superconducting processor

Author: Andersen, Trond I., Lensky, Yuri D., Kechedzhi, Kostyantyn, Drozdov, Ilya, Bengtsson, Andreas, Hong, Sabrina, Morvan, Alexis, Mi, Xiao, Opremcak, Alex, Acharya, Rajeev, Allen, Richard, Ansmann, Markus, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Atalaya, Juan, Babbush, Ryan, Bacon, Dave, Bardin, Joseph C., Bortoli, Gina, Bourassa, Alexandre, Bovaird, Jenna, Brill, Leon, Broughton, Michael, Buckley, Bob B., Buell, David A., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Chen, Zijun, Chiaro, Ben, Chik, Desmond, Chou, Charina, Cogan, Josh, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Curtin, Ben, Debroy, Dripto M., Barba, Alexander Del Toro, Demura, Sean, Dunsworth, Andrew, Eppens, Daniel, Erickson, Catherine, Faoro, Lara, Farhi, Edward, Fatemi, Reza, Ferreira, Vinicius S., Burgos, Leslie Flores, Forati, Ebrahim, Fowler, Austin G., Foxen, Brooks, Giang, William, Gidney, Craig, Gilboa, Dar, Giustina, Marissa, Gosula, Raja, Dau, Alejandro Grajales, Gross, Jonathan A., Habegger, Steve, Hamilton, Michael C., Hansen, Monica, Harrigan, Matthew P., Harrington, Sean D., Heu, Paula, Hilton, Jeremy, Hoffmann, Markus R., Huang, Trent, Huff, Ashley, Huggins, William J., Ioffe, Lev B., Isakov, Sergei V., Iveland, Justin, Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Juhas, Pavol, Kafri, Dvir, Khattar, Tanuj, Khezri, Mostafa, Kieferová, Mária, Kim, Seon, Kitaev, Alexei, Klimov, Paul V., Klots, Andrey R., Korotkov, Alexander N., Kostritsa, Fedor, Kreikebaum, John Mark, Landhuis, David, Laptev, Pavel, Lau, Kim-Ming, Laws, Lily, Lee, Joonho, Lee, Kenny, Lester, Brian J., Lill, Alexander, Liu, Wayne, Locharla, Aditya, Lucero, Erik, Malone, Fionn D., Martin, Orion, McClean, Jarrod R., McCourt, Trevor, McEwen, Matt, Miao, Kevin C., Mieszala, Amanda, Mohseni, Masoud, Montazeri, Shirin, Mount, Emily, Movassagh, Ramis, Mruczkiewicz, Wojciech, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Nersisyan, Ani, Newman, Michael, Ng, Jiun How, Nguyen, Anthony, Nguyen, Murray, Niu, Murphy Yuezhen, O'Brien, Thomas E., Omonije, Seun, Petukhov, Andre, Potter, Rebecca, Pryadko, Leonid P., Quintana, Chris, Rocque, Charles, Rubin, Nicholas C., Saei, Negar, Sank, Daniel, Sankaragomathi, Kannan, Satzinger, Kevin J., Schurkus, Henry F., Schuster, Christopher, Shearn, Michael J., Shorter, Aaron, Shutty, Noah, Shvarts, Vladimir, Skruzny, Jindra, Smith, W. Clarke, Somma, Rolando, Sterling, George, Strain, Doug, Szalay, Marco, Torres, Alfredo, Vidal, Guifre, Villalonga, Benjamin, Heidweiller, Catherine Vollgraff, White, Theodore, Woo, Bryan W. K., Xing, Cheng, Yao, Z. Jamie, Yeh, Ping, Yoo, Juhwan, Young, Grayson, Zalcman, Adam, Zhang, Yaxing, Zhu, Ningfeng, Zobrist, Nicholas, Neven, Hartmut, Boixo, Sergio, Megrant, Anthony, Kelly, Julian, Chen, Yu, Smelyanskiy, Vadim, Kim, Eun-Ah, Aleiner, Igor, and Roushan, Pedram
Subjects: Quantum Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Other Condensed Matter
Abstract: Indistinguishability of particles is a fundamental principle of quantum mechanics. For all elementary and quasiparticles observed to date - including fermions, bosons, and Abelian anyons - this principle guarantees that the braiding of identical particles leaves the system unchanged. However, in two spatial dimensions, an intriguing possibility exists: braiding of non-Abelian anyons causes rotations in a space of topologically degenerate wavefunctions. Hence, it can change the observables of the system without violating the principle of indistinguishability. Despite the well developed mathematical description of non-Abelian anyons and numerous theoretical proposals, the experimental observation of their exchange statistics has remained elusive for decades. Controllable many-body quantum states generated on quantum processors offer another path for exploring these fundamental phenomena. While efforts on conventional solid-state platforms typically involve Hamiltonian dynamics of quasi-particles, superconducting quantum processors allow for directly manipulating the many-body wavefunction via unitary gates. Building on predictions that stabilizer codes can host projective non-Abelian Ising anyons, we implement a generalized stabilizer code and unitary protocol to create and braid them. This allows us to experimentally verify the fusion rules of the anyons and braid them to realize their statistics. We then study the prospect of employing the anyons for quantum computation and utilize braiding to create an entangled state of anyons encoding three logical qubits. Our work provides new insights about non-Abelian braiding and - through the future inclusion of error correction to achieve topological protection - could open a path toward fault-tolerant quantum computing.
Published: 2022

11. Suppressing quantum errors by scaling a surface code logical qubit

Author: Acharya, Rajeev, Aleiner, Igor, Allen, Richard, Andersen, Trond I., Ansmann, Markus, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Atalaya, Juan, Babbush, Ryan, Bacon, Dave, Bardin, Joseph C., Basso, Joao, Bengtsson, Andreas, Boixo, Sergio, Bortoli, Gina, Bourassa, Alexandre, Bovaird, Jenna, Brill, Leon, Broughton, Michael, Buckley, Bob B., Buell, David A., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Chen, Yu, Chen, Zijun, Chiaro, Ben, Cogan, Josh, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Curtin, Ben, Debroy, Dripto M., Barba, Alexander Del Toro, Demura, Sean, Dunsworth, Andrew, Eppens, Daniel, Erickson, Catherine, Faoro, Lara, Farhi, Edward, Fatemi, Reza, Burgos, Leslie Flores, Forati, Ebrahim, Fowler, Austin G., Foxen, Brooks, Giang, William, Gidney, Craig, Gilboa, Dar, Giustina, Marissa, Dau, Alejandro Grajales, Gross, Jonathan A., Habegger, Steve, Hamilton, Michael C., Harrigan, Matthew P., Harrington, Sean D., Higgott, Oscar, Hilton, Jeremy, Hoffmann, Markus, Hong, Sabrina, Huang, Trent, Huff, Ashley, Huggins, William J., Ioffe, Lev B., Isakov, Sergei V., Iveland, Justin, Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Juhas, Pavol, Kafri, Dvir, Kechedzhi, Kostyantyn, Kelly, Julian, Khattar, Tanuj, Khezri, Mostafa, Kieferová, Mária, Kim, Seon, Kitaev, Alexei, Klimov, Paul V., Klots, Andrey R., Korotkov, Alexander N., Kostritsa, Fedor, Kreikebaum, John Mark, Landhuis, David, Laptev, Pavel, Lau, Kim-Ming, Laws, Lily, Lee, Joonho, Lee, Kenny, Lester, Brian J., Lill, Alexander, Liu, Wayne, Locharla, Aditya, Lucero, Erik, Malone, Fionn D., Marshall, Jeffrey, Martin, Orion, McClean, Jarrod R., Mccourt, Trevor, McEwen, Matt, Megrant, Anthony, Costa, Bernardo Meurer, Mi, Xiao, Miao, Kevin C., Mohseni, Masoud, Montazeri, Shirin, Morvan, Alexis, Mount, Emily, Mruczkiewicz, Wojciech, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Nersisyan, Ani, Neven, Hartmut, Newman, Michael, Ng, Jiun How, Nguyen, Anthony, Nguyen, Murray, Niu, Murphy Yuezhen, O'Brien, Thomas E., Opremcak, Alex, Platt, John, Petukhov, Andre, Potter, Rebecca, Pryadko, Leonid P., Quintana, Chris, Roushan, Pedram, Rubin, Nicholas C., Saei, Negar, Sank, Daniel, Sankaragomathi, Kannan, Satzinger, Kevin J., Schurkus, Henry F., Schuster, Christopher, Shearn, Michael J., Shorter, Aaron, Shvarts, Vladimir, Skruzny, Jindra, Smelyanskiy, Vadim, Smith, W. Clarke, Sterling, George, Strain, Doug, Szalay, Marco, Torres, Alfredo, Vidal, Guifre, Villalonga, Benjamin, Heidweiller, Catherine Vollgraff, White, Theodore, Xing, Cheng, Yao, Z. Jamie, Yeh, Ping, Yoo, Juhwan, Young, Grayson, Zalcman, Adam, Zhang, Yaxing, and Zhu, Ningfeng
Subjects: Quantum Physics
Abstract: Practical quantum computing will require error rates that are well below what is achievable with physical qubits. Quantum error correction offers a path to algorithmically-relevant error rates by encoding logical qubits within many physical qubits, where increasing the number of physical qubits enhances protection against physical errors. However, introducing more qubits also increases the number of error sources, so the density of errors must be sufficiently low in order for logical performance to improve with increasing code size. Here, we report the measurement of logical qubit performance scaling across multiple code sizes, and demonstrate that our system of superconducting qubits has sufficient performance to overcome the additional errors from increasing qubit number. We find our distance-5 surface code logical qubit modestly outperforms an ensemble of distance-3 logical qubits on average, both in terms of logical error probability over 25 cycles and logical error per cycle ($2.914\%\pm 0.016\%$ compared to $3.028\%\pm 0.023\%$). To investigate damaging, low-probability error sources, we run a distance-25 repetition code and observe a $1.7\times10^{-6}$ logical error per round floor set by a single high-energy event ($1.6\times10^{-7}$ when excluding this event). We are able to accurately model our experiment, and from this model we can extract error budgets that highlight the biggest challenges for future systems. These results mark the first experimental demonstration where quantum error correction begins to improve performance with increasing qubit number, illuminating the path to reaching the logical error rates required for computation., Comment: Main text: 6 pages, 4 figures. v2: Update author list, references, Fig. S12, Table IV
Published: 2022

12. Formation of robust bound states of interacting microwave photons

Author: Morvan, Alexis, Andersen, Trond I., Mi, Xiao, Neill, Charles, Petukhov, Andre, Kechedzhi, Kostyantyn, Abanin, Dmitry, Acharya, Rajeev, Arute, Frank, Arya, Kunal, Asfaw, Abraham, Atalaya, Juan, Babbush, Ryan, Bacon, Dave, Bardin, Joseph C., Basso, Joao, Bengtsson, Andreas, Bortoli, Gina, Bourassa, Alexandre, Bovaird, Jenna, Brill, Leon, Broughton, Michael, Buckley, Bob B., Buell, David A., Burger, Tim, Burkett, Brian, Bushnell, Nicholas, Chen, Zijun, Chiaro, Ben, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Curtin, Ben, Debroy, Dripto M., Barba, Alexander Del Toro, Demura, Sean, Dunsworth, Andrew, Eppens, Daniel, Erickson, Catherine, Faoro, Lara, Farhi, Edward, Fatemi, Reza, Burgos, Leslie Flores, Forati, Ebrahim, Fowler, Austin G., Foxen, Brooks, Giang, William, Gidney, Craig, Gilboa, Dar, Giustina, Marissa, Dau, Alejandro Grajales, Gross, Jonathan A., Habegger, Steve, Hamilton, Michael C., Harrigan, Matthew P., Harrington, Sean D., Hilton, Jeremy, Hoffmann, Markus, Hong, Sabrina, Huang, Trent, Huff, Ashley, Huggins, William J., Isakov, Sergei V., Iveland, Justin, Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Juhas, Pavol, Kafri, Dvir, Khattar, Tanuj, Khezri, Mostafa, Kieferova, Marika, Kim, Seon, Kitaev, Alexei, Klimov, Paul V., Klots, Andrey R., Korotkov, Alexander N., Kostritsa, Fedor, Kreikebaum, John Mark, Landhuis, David, Laptev, Pavel, Lau, Kim-Ming, Laws, Lily, Lee, Joonho, Lee, Kenny, Lester, Brian J., Lill, Alexander, Liu, Wayne, Locharla, Aditya, Lucero, Erik, Malone, Fionn D., Martin, Orion, McClean, Jarrod R., McEwen, Matt, Costa, Bernardo Meurer, Miao, Kevin C., Mohseni, Masoud, Montazeri, Shirin, Mount, Emily, Mruczkiewicz, Wojciech, Naaman, Ofer, Neeley, Matthew, Nersisyan, Ani, Newman, Michael, Nguyen, Anthony, Nguyen, Murray, Niu, Murphy Yuezhen, O'Brien, Thomas E., Olenewa, Ricardo, Opremcak, Alex, Potter, Rebecca, Quintana, Chris, Rubin, Nicholas C., Saei, Negar, Sank, Daniel, Sankaragomathi, Kannan, Satzinger, Kevin J., Schurkus, Henry F., Schuster, Christopher, Shearn, Michael J., Shorter, Aaron, Shvarts, Vladimir, Skruzny, Jindra, Smith, W. Clarke, Sterling, George, Strain, Doug, Su, Yuan, Szalay, Marco, Torres, Alfredo, Vidal, Guifre, Villalonga, Benjamin, Heidweiller, Catherine Vollgraff, White, Theodore, Xing, Cheng, Yao, Z. Jamie, Yeh, Ping, Yoo, Juhwan, Zalcman, Adam, Zhang, Yaxing, Zhu, Ningfeng, Neven, Hartmut, Boixo, Sergio, Megrant, Anthony, Kelly, Julian, Chen, Yu, Smelyanskiy, Vadim, Aleiner, Igor, Ioffe, Lev B., and Roushan, Pedram
Subjects: Quantum Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Other Condensed Matter
Abstract: Systems of correlated particles appear in many fields of science and represent some of the most intractable puzzles in nature. The computational challenge in these systems arises when interactions become comparable to other energy scales, which makes the state of each particle depend on all other particles. The lack of general solutions for the 3-body problem and acceptable theory for strongly correlated electrons shows that our understanding of correlated systems fades when the particle number or the interaction strength increases. One of the hallmarks of interacting systems is the formation of multi-particle bound states. In a ring of 24 superconducting qubits, we develop a high fidelity parameterizable fSim gate that we use to implement the periodic quantum circuit of the spin-1/2 XXZ model, an archetypal model of interaction. By placing microwave photons in adjacent qubit sites, we study the propagation of these excitations and observe their bound nature for up to 5 photons. We devise a phase sensitive method for constructing the few-body spectrum of the bound states and extract their pseudo-charge by introducing a synthetic flux. By introducing interactions between the ring and additional qubits, we observe an unexpected resilience of the bound states to integrability breaking. This finding goes against the common wisdom that bound states in non-integrable systems are unstable when their energies overlap with the continuum spectrum. Our work provides experimental evidence for bound states of interacting photons and discovers their stability beyond the integrability limit., Comment: 7 pages + 15 pages supplements
Published: 2022
Full Text: View/download PDF

13. Noise-resilient Edge Modes on a Chain of Superconducting Qubits

Author: Mi, Xiao, Sonner, Michael, Niu, Murphy Yuezhen, Lee, Kenneth W., Foxen, Brooks, Acharya, Rajeev, Aleiner, Igor, Andersen, Trond I., Arute, Frank, Arya, Kunal, Asfaw, Abraham, Atalaya, Juan, Babbush, Ryan, Bacon, Dave, Bardin, Joseph C., Basso, Joao, Bengtsson, Andreas, Bortoli, Gina, Bourassa, Alexandre, Brill, Leon, Broughton, Michael, Buckley, Bob B., Buell, David A., Burkett, Brian, Bushnell, Nicholas, Chen, Zijun, Chiaro, Benjamin, Collins, Roberto, Conner, Paul, Courtney, William, Crook, Alexander L., Debroy, Dripto M., Demura, Sean, Dunsworth, Andrew, Eppens, Daniel, Erickson, Catherine, Faoro, Lara, Farhi, Edward, Fatemi, Reza, Flores, Leslie, Forati, Ebrahim, Fowler, Austin G., Giang, William, Gidney, Craig, Gilboa, Dar, Giustina, Marissa, Dau, Alejandro Grajales, Gross, Jonathan A., Habegger, Steve, Harrigan, Matthew P., Hilton, Jeremy, Hoffmann, Markus, Hong, Sabrina, Huang, Trent, Huff, Ashley, Huggins, William J., Ioffe, Lev B., Isakov, Sergei V., Iveland, Justin, Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Kafri, Dvir, Kechedzhi, Kostyantyn, Khattar, Tanuj, Kim, Seon, Kitaev, Alexei, Klimov, Paul V., Klots, Andrey R., Korotkov, Alexander N., Kostritsa, Fedor, Kreikebaum, J. M., Landhuis, David, Laptev, Pavel, Lau, Kim-Ming, Lee, Joonho, Laws, Lily, Liu, Wayne, Locharla, Aditya, Lucero, Erik, Martin, Orion, McClean, Jarrod R., McEwen, Matt, Costa, Bernardo Meurer, Miao, Kevin C., Mohseni, Masoud, Montazeri, Shirin, Morvan, Alexis, Mount, Emily, Mruczkiewicz, Wojciech, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Newman, Michael, O'Brien, Thomas E., Opremcak, Alex, Petukhov, Andre, Potter, Rebecca, Quintana, Chris, Rubin, Nicholas C., Saei, Negar, Sank, Daniel, Sankaragomathi, Kannan, Satzinger, Kevin J., Schuster, Christopher, Shearn, Michael J., Shvarts, Vladimir, Strain, Doug, Su, Yuan, Szalay, Marco, Vidal, Guifre, Villalonga, Benjamin, Vollgraff-Heidweiller, Catherine, White, Theodore, Yao, Z. Jamie, Yeh, Ping, Yoo, Juhwan, Zalcman, Adam, Zhang, Yaxing, Zhu, Ningfeng, Neven, Hartmut, Boixo, Sergio, Megrant, Anthony, Chen, Yu, Kelly, Julian, Smelyanskiy, Vadim, Abanin, Dmitry A., and Roushan, Pedram
Subjects: Quantum Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Other Condensed Matter
Abstract: Inherent symmetry of a quantum system may protect its otherwise fragile states. Leveraging such protection requires testing its robustness against uncontrolled environmental interactions. Using 47 superconducting qubits, we implement the one-dimensional kicked Ising model which exhibits non-local Majorana edge modes (MEMs) with $\mathbb{Z}_2$ parity symmetry. Remarkably, we find that any multi-qubit Pauli operator overlapping with the MEMs exhibits a uniform late-time decay rate comparable to single-qubit relaxation rates, irrespective of its size or composition. This characteristic allows us to accurately reconstruct the exponentially localized spatial profiles of the MEMs. Furthermore, the MEMs are found to be resilient against certain symmetry-breaking noise owing to a prethermalization mechanism. Our work elucidates the complex interplay between noise and symmetry-protected edge modes in a solid-state environment.
Published: 2022
Full Text: View/download PDF

14. Observation of Time-Crystalline Eigenstate Order on a Quantum Processor

Author: Mi, Xiao, Ippoliti, Matteo, Quintana, Chris, Greene, Ami, Chen, Zijun, Gross, Jonathan, Arute, Frank, Arya, Kunal, Atalaya, Juan, Babbush, Ryan, Bardin, Joseph C., Basso, Joao, Bengtsson, Andreas, Bilmes, Alexander, Bourassa, Alexandre, Brill, Leon, Broughton, Michael, Buckley, Bob B., Buell, David A., Burkett, Brian, Bushnell, Nicholas, Chiaro, Benjamin, Collins, Roberto, Courtney, William, Debroy, Dripto, Demura, Sean, Derk, Alan R., Dunsworth, Andrew, Eppens, Daniel, Erickson, Catherine, Farhi, Edward, Fowler, Austin G., Foxen, Brooks, Gidney, Craig, Giustina, Marissa, Harrigan, Matthew P., Harrington, Sean D., Hilton, Jeremy, Ho, Alan, Hong, Sabrina, Huang, Trent, Huff, Ashley, Huggins, William J., Ioffe, L. B., Isakov, Sergei V., Iveland, Justin, Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Kafri, Dvir, Khattar, Tanuj, Kim, Seon, Kitaev, Alexei, Klimov, Paul V., Korotkov, Alexander N., Kostritsa, Fedor, Landhuis, David, Laptev, Pavel, Lee, Joonho, Lee, Kenny, Locharla, Aditya, Lucero, Erik, Martin, Orion, McClean, Jarrod R., McCourt, Trevor, McEwen, Matt, Miao, Kevin C., Mohseni, Masoud, Montazeri, Shirin, Mruczkiewicz, Wojciech, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Newman, Michael, Niu, Murphy Yuezhen, Brien, Thomas E. O\', Opremcak, Alex, Ostby, Eric, Pato, Balint, Petukhov, Andre, Rubin, Nicholas C., Sank, Daniel, Satzinger, Kevin J., Shvarts, Vladimir, Su, Yuan, Strain, Doug, Szalay, Marco, Trevithick, Matthew D., Villalonga, Benjamin, White, Theodore, Yao, Z. Jamie, Yeh, Ping, Yoo, Juhwan, Zalcman, Adam, Neven, Hartmut, Boixo, Sergio, Smelyanskiy, Vadim, Megrant, Anthony, Kelly, Julian, Chen, Yu, Sondhi, S. L., Moessner, Roderich, Kechedzhi, Kostyantyn, Khemani, Vedika, and Roushan, Pedram
Subjects: Quantum Physics, Condensed Matter - Disordered Systems and Neural Networks, Condensed Matter - Statistical Mechanics, Condensed Matter - Strongly Correlated Electrons
Abstract: Quantum many-body systems display rich phase structure in their low-temperature equilibrium states. However, much of nature is not in thermal equilibrium. Remarkably, it was recently predicted that out-of-equilibrium systems can exhibit novel dynamical phases that may otherwise be forbidden by equilibrium thermodynamics, a paradigmatic example being the discrete time crystal (DTC). Concretely, dynamical phases can be defined in periodically driven many-body localized systems via the concept of eigenstate order. In eigenstate-ordered phases, the entire many-body spectrum exhibits quantum correlations and long-range order, with characteristic signatures in late-time dynamics from all initial states. It is, however, challenging to experimentally distinguish such stable phases from transient phenomena, wherein few select states can mask typical behavior. Here we implement a continuous family of tunable CPHASE gates on an array of superconducting qubits to experimentally observe an eigenstate-ordered DTC. We demonstrate the characteristic spatiotemporal response of a DTC for generic initial states. Our work employs a time-reversal protocol that discriminates external decoherence from intrinsic thermalization, and leverages quantum typicality to circumvent the exponential cost of densely sampling the eigenspectrum. In addition, we locate the phase transition out of the DTC with an experimental finite-size analysis. These results establish a scalable approach to study non-equilibrium phases of matter on current quantum processors.
Published: 2021
Full Text: View/download PDF

15. Time-crystalline eigenstate order on a quantum processor

Author: Mi, Xiao, Ippoliti, Matteo, Quintana, Chris, Greene, Ami, Chen, Zijun, Gross, Jonathan, Arute, Frank, Arya, Kunal, Atalaya, Juan, Babbush, Ryan, Bardin, Joseph C, Basso, Joao, Bengtsson, Andreas, Bilmes, Alexander, Bourassa, Alexandre, Brill, Leon, Broughton, Michael, Buckley, Bob B, Buell, David A, Burkett, Brian, Bushnell, Nicholas, Chiaro, Benjamin, Collins, Roberto, Courtney, William, Debroy, Dripto, Demura, Sean, Derk, Alan R, Dunsworth, Andrew, Eppens, Daniel, Erickson, Catherine, Farhi, Edward, Fowler, Austin G, Foxen, Brooks, Gidney, Craig, Giustina, Marissa, Harrigan, Matthew P, Harrington, Sean D, Hilton, Jeremy, Ho, Alan, Hong, Sabrina, Huang, Trent, Huff, Ashley, Huggins, William J, Ioffe, LB, Isakov, Sergei V, Iveland, Justin, Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Kafri, Dvir, Khattar, Tanuj, Kim, Seon, Kitaev, Alexei, Klimov, Paul V, Korotkov, Alexander N, Kostritsa, Fedor, Landhuis, David, Laptev, Pavel, Lee, Joonho, Lee, Kenny, Locharla, Aditya, Lucero, Erik, Martin, Orion, McClean, Jarrod R, McCourt, Trevor, McEwen, Matt, Miao, Kevin C, Mohseni, Masoud, Montazeri, Shirin, Mruczkiewicz, Wojciech, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Newman, Michael, Niu, Murphy Yuezhen, O’Brien, Thomas E, Opremcak, Alex, Ostby, Eric, Pato, Balint, Petukhov, Andre, Rubin, Nicholas C, Sank, Daniel, Satzinger, Kevin J, Shvarts, Vladimir, Su, Yuan, Strain, Doug, Szalay, Marco, Trevithick, Matthew D, Villalonga, Benjamin, White, Theodore, Yao, Z Jamie, Yeh, Ping, Yoo, Juhwan, Zalcman, Adam, Neven, Hartmut, Boixo, Sergio, Smelyanskiy, Vadim, Megrant, Anthony, Kelly, Julian, and Chen, Yu
Subjects: Cold Temperature, Phase Transition, Thermodynamics, General Science & Technology
Abstract: Quantum many-body systems display rich phase structure in their low-temperature equilibrium states1. However, much of nature is not in thermal equilibrium. Remarkably, it was recently predicted that out-of-equilibrium systems can exhibit novel dynamical phases2-8 that may otherwise be forbidden by equilibrium thermodynamics, a paradigmatic example being the discrete time crystal (DTC)7,9-15. Concretely, dynamical phases can be defined in periodically driven many-body-localized (MBL) systems via the concept of eigenstate order7,16,17. In eigenstate-ordered MBL phases, the entire many-body spectrum exhibits quantum correlations and long-range order, with characteristic signatures in late-time dynamics from all initial states. It is, however, challenging to experimentally distinguish such stable phases from transient phenomena, or from regimes in which the dynamics of a few select states can mask typical behaviour. Here we implement tunable controlled-phase (CPHASE) gates on an array of superconducting qubits to experimentally observe an MBL-DTC and demonstrate its characteristic spatiotemporal response for generic initial states7,9,10. Our work employs a time-reversal protocol to quantify the impact of external decoherence, and leverages quantum typicality to circumvent the exponential cost of densely sampling the eigenspectrum. Furthermore, we locate the phase transition out of the DTC with an experimental finite-size analysis. These results establish a scalable approach to studying non-equilibrium phases of matter on quantum processors.
Published: 2022

16. Resolving catastrophic error bursts from cosmic rays in large arrays of superconducting qubits

Author: McEwen, Matt, Faoro, Lara, Arya, Kunal, Dunsworth, Andrew, Huang, Trent, Kim, Seon, Burkett, Brian, Fowler, Austin, Arute, Frank, Bardin, Joseph C., Bengtsson, Andreas, Bilmes, Alexander, Buckley, Bob B., Bushnell, Nicholas, Chen, Zijun, Collins, Roberto, Demura, Sean, Derk, Alan R., Erickson, Catherine, Giustina, Marissa, Harrington, Sean D., Hong, Sabrina, Jeffrey, Evan, Kelly, Julian, Klimov, Paul V., Kostritsa, Fedor, Laptev, Pavel, Locharla, Aditya, Mi, Xiao, Miao, Kevin C., Montazeri, Shirin, Mutus, Josh, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Opremcak, Alex, Quintana, Chris, Redd, Nicholas, Roushan, Pedram, Sank, Daniel, Satzinger, Kevin J., Shvarts, Vladimir, White, Theodore, Yao, Z. Jamie, Yeh, Ping, Yoo, Juhwan, Chen, Yu, Smelyanskiy, Vadim, Martinis, John M., Neven, Hartmut, Megrant, Anthony, Ioffe, Lev, and Barends, Rami
Subjects: Quantum Physics
Abstract: Scalable quantum computing can become a reality with error correction, provided coherent qubits can be constructed in large arrays. The key premise is that physical errors can remain both small and sufficiently uncorrelated as devices scale, so that logical error rates can be exponentially suppressed. However, energetic impacts from cosmic rays and latent radioactivity violate both of these assumptions. An impinging particle ionizes the substrate, radiating high energy phonons that induce a burst of quasiparticles, destroying qubit coherence throughout the device. High-energy radiation has been identified as a source of error in pilot superconducting quantum devices, but lacking a measurement technique able to resolve a single event in detail, the effect on large scale algorithms and error correction in particular remains an open question. Elucidating the physics involved requires operating large numbers of qubits at the same rapid timescales as in error correction, exposing the event's evolution in time and spread in space. Here, we directly observe high-energy rays impacting a large-scale quantum processor. We introduce a rapid space and time-multiplexed measurement method and identify large bursts of quasiparticles that simultaneously and severely limit the energy coherence of all qubits, causing chip-wide failure. We track the events from their initial localised impact to high error rates across the chip. Our results provide direct insights into the scale and dynamics of these damaging error bursts in large-scale devices, and highlight the necessity of mitigation to enable quantum computing to scale.
Published: 2021
Full Text: View/download PDF

17. Exponential suppression of bit or phase flip errors with repetitive error correction

Author: Chen, Zijun, Satzinger, Kevin J., Atalaya, Juan, Korotkov, Alexander N., Dunsworth, Andrew, Sank, Daniel, Quintana, Chris, McEwen, Matt, Barends, Rami, Klimov, Paul V., Hong, Sabrina, Jones, Cody, Petukhov, Andre, Kafri, Dvir, Demura, Sean, Burkett, Brian, Gidney, Craig, Fowler, Austin G., Putterman, Harald, Aleiner, Igor, Arute, Frank, Arya, Kunal, Babbush, Ryan, Bardin, Joseph C., Bengtsson, Andreas, Bourassa, Alexandre, Broughton, Michael, Buckley, Bob B., Buell, David A., Bushnell, Nicholas, Chiaro, Benjamin, Collins, Roberto, Courtney, William, Derk, Alan R., Eppens, Daniel, Erickson, Catherine, Farhi, Edward, Foxen, Brooks, Giustina, Marissa, Gross, Jonathan A., Harrigan, Matthew P., Harrington, Sean D., Hilton, Jeremy, Ho, Alan, Huang, Trent, Huggins, William J., Ioffe, L. B., Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Kechedzhi, Kostyantyn, Kim, Seon, Kostritsa, Fedor, Landhuis, David, Laptev, Pavel, Lucero, Erik, Martin, Orion, McClean, Jarrod R., McCourt, Trevor, Mi, Xiao, Miao, Kevin C., Mohseni, Masoud, Mruczkiewicz, Wojciech, Mutus, Josh, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Newman, Michael, Niu, Murphy Yuezhen, O'Brien, Thomas E., Opremcak, Alex, Ostby, Eric, Pató, Bálint, Redd, Nicholas, Roushan, Pedram, Rubin, Nicholas C., Shvarts, Vladimir, Strain, Doug, Szalay, Marco, Trevithick, Matthew D., Villalonga, Benjamin, White, Theodore, Yao, Z. Jamie, Yeh, Ping, Zalcman, Adam, Neven, Hartmut, Boixo, Sergio, Smelyanskiy, Vadim, Chen, Yu, Megrant, Anthony, and Kelly, Julian
Subjects: Quantum Physics
Abstract: Realizing the potential of quantum computing will require achieving sufficiently low logical error rates. Many applications call for error rates in the $10^{-15}$ regime, but state-of-the-art quantum platforms typically have physical error rates near $10^{-3}$. Quantum error correction (QEC) promises to bridge this divide by distributing quantum logical information across many physical qubits so that errors can be detected and corrected. Logical errors are then exponentially suppressed as the number of physical qubits grows, provided that the physical error rates are below a certain threshold. QEC also requires that the errors are local and that performance is maintained over many rounds of error correction, two major outstanding experimental challenges. Here, we implement 1D repetition codes embedded in a 2D grid of superconducting qubits which demonstrate exponential suppression of bit or phase-flip errors, reducing logical error per round by more than $100\times$ when increasing the number of qubits from 5 to 21. Crucially, this error suppression is stable over 50 rounds of error correction. We also introduce a method for analyzing error correlations with high precision, and characterize the locality of errors in a device performing QEC for the first time. Finally, we perform error detection using a small 2D surface code logical qubit on the same device, and show that the results from both 1D and 2D codes agree with numerical simulations using a simple depolarizing error model. These findings demonstrate that superconducting qubits are on a viable path towards fault tolerant quantum computing.
Published: 2021
Full Text: View/download PDF

18. Information Scrambling in Computationally Complex Quantum Circuits

Author: Mi, Xiao, Roushan, Pedram, Quintana, Chris, Mandra, Salvatore, Marshall, Jeffrey, Neill, Charles, Arute, Frank, Arya, Kunal, Atalaya, Juan, Babbush, Ryan, Bardin, Joseph C., Barends, Rami, Bengtsson, Andreas, Boixo, Sergio, Bourassa, Alexandre, Broughton, Michael, Buckley, Bob B., Buell, David A., Burkett, Brian, Bushnell, Nicholas, Chen, Zijun, Chiaro, Benjamin, Collins, Roberto, Courtney, William, Demura, Sean, Derk, Alan R., Dunsworth, Andrew, Eppens, Daniel, Erickson, Catherine, Farhi, Edward, Fowler, Austin G., Foxen, Brooks, Gidney, Craig, Giustina, Marissa, Gross, Jonathan A., Harrigan, Matthew P., Harrington, Sean D., Hilton, Jeremy, Ho, Alan, Hong, Sabrina, Huang, Trent, Huggins, William J., Ioffe, L. B., Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Kafri, Dvir, Kelly, Julian, Kim, Seon, Kitaev, Alexei, Klimov, Paul V., Korotkov, Alexander N., Kostritsa, Fedor, Landhuis, David, Laptev, Pavel, Lucero, Erik, Martin, Orion, McClean, Jarrod R., McCourt, Trevor, McEwen, Matt, Megrant, Anthony, Miao, Kevin C., Mohseni, Masoud, Mruczkiewicz, Wojciech, Mutus, Josh, Naaman, Ofer, Neeley, Matthew, Newman, Michael, Niu, Murphy Yuezhen, O'Brien, Thomas E., Opremcak, Alex, Ostby, Eric, Pato, Balint, Petukhov, Andre, Redd, Nicholas, Rubin, Nicholas C., Sank, Daniel, Satzinger, Kevin J., Shvarts, Vladimir, Strain, Doug, Szalay, Marco, Trevithick, Matthew D., Villalonga, Benjamin, White, Theodore, Yao, Z. Jamie, Yeh, Ping, Zalcman, Adam, Neven, Hartmut, Aleiner, Igor, Kechedzhi, Kostyantyn, Smelyanskiy, Vadim, and Chen, Yu
Subjects: Quantum Physics, Condensed Matter - Strongly Correlated Electrons, High Energy Physics - Theory
Abstract: Interaction in quantum systems can spread initially localized quantum information into the many degrees of freedom of the entire system. Understanding this process, known as quantum scrambling, is the key to resolving various conundrums in physics. Here, by measuring the time-dependent evolution and fluctuation of out-of-time-order correlators, we experimentally investigate the dynamics of quantum scrambling on a 53-qubit quantum processor. We engineer quantum circuits that distinguish the two mechanisms associated with quantum scrambling, operator spreading and operator entanglement, and experimentally observe their respective signatures. We show that while operator spreading is captured by an efficient classical model, operator entanglement requires exponentially scaled computational resources to simulate. These results open the path to studying complex and practically relevant physical observables with near-term quantum processors.
Published: 2021
Full Text: View/download PDF

19. Observation of separated dynamics of charge and spin in the Fermi-Hubbard model

Author: Arute, Frank, Arya, Kunal, Babbush, Ryan, Bacon, Dave, Bardin, Joseph C., Barends, Rami, Bengtsson, Andreas, Boixo, Sergio, Broughton, Michael, Buckley, Bob B., Buell, David A., Burkett, Brian, Bushnell, Nicholas, Chen, Yu, Chen, Zijun, Chen, Yu-An, Chiaro, Ben, Collins, Roberto, Cotton, Stephen J., Courtney, William, Demura, Sean, Derk, Alan, Dunsworth, Andrew, Eppens, Daniel, Eckl, Thomas, Erickson, Catherine, Farhi, Edward, Fowler, Austin, Foxen, Brooks, Gidney, Craig, Giustina, Marissa, Graff, Rob, Gross, Jonathan A., Habegger, Steve, Harrigan, Matthew P., Ho, Alan, Hong, Sabrina, Huang, Trent, Huggins, William, Ioffe, Lev B., Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Kafri, Dvir, Kechedzhi, Kostyantyn, Kelly, Julian, Kim, Seon, Klimov, Paul V., Korotkov, Alexander N., Kostritsa, Fedor, Landhuis, David, Laptev, Pavel, Lindmark, Mike, Lucero, Erik, Marthaler, Michael, Martin, Orion, Martinis, John M., Marusczyk, Anika, McArdle, Sam, McClean, Jarrod R., McCourt, Trevor, McEwen, Matt, Megrant, Anthony, Mejuto-Zaera, Carlos, Mi, Xiao, Mohseni, Masoud, Mruczkiewicz, Wojciech, Mutus, Josh, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Neven, Hartmut, Newman, Michael, Niu, Murphy Yuezhen, O'Brien, Thomas E., Ostby, Eric, Pató, Bálint, Petukhov, Andre, Putterman, Harald, Quintana, Chris, Reiner, Jan-Michael, Roushan, Pedram, Rubin, Nicholas C., Sank, Daniel, Satzinger, Kevin J., Smelyanskiy, Vadim, Strain, Doug, Sung, Kevin J., Schmitteckert, Peter, Szalay, Marco, Tubman, Norm M., Vainsencher, Amit, White, Theodore, Vogt, Nicolas, Yao, Z. Jamie, Yeh, Ping, Zalcman, Adam, and Zanker, Sebastian
Subjects: Quantum Physics
Abstract: Strongly correlated quantum systems give rise to many exotic physical phenomena, including high-temperature superconductivity. Simulating these systems on quantum computers may avoid the prohibitively high computational cost incurred in classical approaches. However, systematic errors and decoherence effects presented in current quantum devices make it difficult to achieve this. Here, we simulate the dynamics of the one-dimensional Fermi-Hubbard model using 16 qubits on a digital superconducting quantum processor. We observe separations in the spreading velocities of charge and spin densities in the highly excited regime, a regime that is beyond the conventional quasiparticle picture. To minimize systematic errors, we introduce an accurate gate calibration procedure that is fast enough to capture temporal drifts of the gate parameters. We also employ a sequence of error-mitigation techniques to reduce decoherence effects and residual systematic errors. These procedures allow us to simulate the time evolution of the model faithfully despite having over 600 two-qubit gates in our circuits. Our experiment charts a path to practical quantum simulation of strongly correlated phenomena using available quantum devices., Comment: 20 pages, 15 figures
Published: 2020

20. Quantum Approximate Optimization of Non-Planar Graph Problems on a Planar Superconducting Processor

Author: Harrigan, Matthew P., Sung, Kevin J., Neeley, Matthew, Satzinger, Kevin J., Arute, Frank, Arya, Kunal, Atalaya, Juan, Bardin, Joseph C., Barends, Rami, Boixo, Sergio, Broughton, Michael, Buckley, Bob B., Buell, David A., Burkett, Brian, Bushnell, Nicholas, Chen, Yu, Chen, Zijun, Chiaro, Ben, Collins, Roberto, Courtney, William, Demura, Sean, Dunsworth, Andrew, Eppens, Daniel, Fowler, Austin, Foxen, Brooks, Gidney, Craig, Giustina, Marissa, Graff, Rob, Habegger, Steve, Ho, Alan, Hong, Sabrina, Huang, Trent, Ioffe, L. B., Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Kafri, Dvir, Kechedzhi, Kostyantyn, Kelly, Julian, Kim, Seon, Klimov, Paul V., Korotkov, Alexander N., Kostritsa, Fedor, Landhuis, David, Laptev, Pavel, Lindmark, Mike, Leib, Martin, Martin, Orion, Martinis, John M., McClean, Jarrod R., McEwen, Matt, Megrant, Anthony, Mi, Xiao, Mohseni, Masoud, Mruczkiewicz, Wojciech, Mutus, Josh, Naaman, Ofer, Neill, Charles, Neukart, Florian, Niu, Murphy Yuezhen, O'Brien, Thomas E., O'Gorman, Bryan, Ostby, Eric, Petukhov, Andre, Putterman, Harald, Quintana, Chris, Roushan, Pedram, Rubin, Nicholas C., Sank, Daniel, Skolik, Andrea, Smelyanskiy, Vadim, Strain, Doug, Streif, Michael, Szalay, Marco, Vainsencher, Amit, White, Theodore, Yao, Z. Jamie, Yeh, Ping, Zalcman, Adam, Zhou, Leo, Neven, Hartmut, Bacon, Dave, Lucero, Erik, Farhi, Edward, and Babbush, Ryan
Subjects: Quantum Physics
Abstract: We demonstrate the application of the Google Sycamore superconducting qubit quantum processor to combinatorial optimization problems with the quantum approximate optimization algorithm (QAOA). Like past QAOA experiments, we study performance for problems defined on the (planar) connectivity graph of our hardware; however, we also apply the QAOA to the Sherrington-Kirkpatrick model and MaxCut, both high dimensional graph problems for which the QAOA requires significant compilation. Experimental scans of the QAOA energy landscape show good agreement with theory across even the largest instances studied (23 qubits) and we are able to perform variational optimization successfully. For problems defined on our hardware graph we obtain an approximation ratio that is independent of problem size and observe, for the first time, that performance increases with circuit depth. For problems requiring compilation, performance decreases with problem size but still provides an advantage over random guessing for circuits involving several thousand gates. This behavior highlights the challenge of using near-term quantum computers to optimize problems on graphs differing from hardware connectivity. As these graphs are more representative of real world instances, our results advocate for more emphasis on such problems in the developing tradition of using the QAOA as a holistic, device-level benchmark of quantum processors., Comment: 19 pages, 15 figures
Published: 2020
Full Text: View/download PDF

21. Hartree-Fock on a superconducting qubit quantum computer

Author: Arute, Frank, Arya, Kunal, Babbush, Ryan, Bacon, Dave, Bardin, Joseph C., Barends, Rami, Boixo, Sergio, Broughton, Michael, Buckley, Bob B., Buell, David A., Burkett, Brian, Bushnell, Nicholas, Chen, Yu, Chen, Zijun, Chiaro, Benjamin, Collins, Roberto, Courtney, William, Demura, Sean, Dunsworth, Andrew, Eppens, Daniel, Farhi, Edward, Fowler, Austin, Foxen, Brooks, Gidney, Craig, Giustina, Marissa, Graff, Rob, Habegger, Steve, Harrigan, Matthew P., Ho, Alan, Hong, Sabrina, Huang, Trent, Huggins, William J., Ioffe, Lev, Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Kafri, Dvir, Kechedzhi, Kostyantyn, Kelly, Julian, Kim, Seon, Klimov, Paul V., Korotkov, Alexander, Kostritsa, Fedor, Landhuis, David, Laptev, Pavel, Lindmark, Mike, Lucero, Erik, Martin, Orion, Martinis, John M., McClean, Jarrod R., McEwen, Matt, Megrant, Anthony, Mi, Xiao, Mohseni, Masoud, Mruczkiewicz, Wojciech, Mutus, Josh, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Neven, Hartmut, Niu, Murphy Yuezhen, O'Brien, Thomas E., Ostby, Eric, Petukhov, Andre, Putterman, Harald, Quintana, Chris, Roushan, Pedram, Rubin, Nicholas C., Sank, Daniel, Satzinger, Kevin J., Smelyanskiy, Vadim, Strain, Doug, Sung, Kevin J., Szalay, Marco, Takeshita, Tyler Y., Vainsencher, Amit, White, Theodore, Wiebe, Nathan, Yao, Z. Jamie, Yeh, Ping, and Zalcman, Adam
Subjects: Quantum Physics, Physics - Chemical Physics
Abstract: As the search continues for useful applications of noisy intermediate scale quantum devices, variational simulations of fermionic systems remain one of the most promising directions. Here, we perform a series of quantum simulations of chemistry the largest of which involved a dozen qubits, 78 two-qubit gates, and 114 one-qubit gates. We model the binding energy of ${\rm H}_6$, ${\rm H}_8$, ${\rm H}_{10}$ and ${\rm H}_{12}$ chains as well as the isomerization of diazene. We also demonstrate error-mitigation strategies based on $N$-representability which dramatically improve the effective fidelity of our experiments. Our parameterized ansatz circuits realize the Givens rotation approach to non-interacting fermion evolution, which we variationally optimize to prepare the Hartree-Fock wavefunction. This ubiquitous algorithmic primitive corresponds to a rotation of the orbital basis and is required by many proposals for correlated simulations of molecules and Hubbard models. Because non-interacting fermion evolutions are classically tractable to simulate, yet still generate highly entangled states over the computational basis, we use these experiments to benchmark the performance of our hardware while establishing a foundation for scaling up more complex correlated quantum simulations of chemistry., Comment: updated link to experiment code, new version containing expanded data sets and corrected figure label
Published: 2020
Full Text: View/download PDF

22. Exponential suppression of bit or phase errors with cyclic error correction

Author: Chen, Zijun, Satzinger, Kevin J, Atalaya, Juan, Korotkov, Alexander N, Dunsworth, Andrew, Sank, Daniel, Quintana, Chris, McEwen, Matt, Barends, Rami, Klimov, Paul V, Hong, Sabrina, Jones, Cody, Petukhov, Andre, Kafri, Dvir, Demura, Sean, Burkett, Brian, Gidney, Craig, Fowler, Austin G, Paler, Alexandru, Putterman, Harald, Aleiner, Igor, Arute, Frank, Arya, Kunal, Babbush, Ryan, Bardin, Joseph C, Bengtsson, Andreas, Bourassa, Alexandre, Broughton, Michael, Buckley, Bob B, Buell, David A, Bushnell, Nicholas, Chiaro, Benjamin, Collins, Roberto, Courtney, William, Derk, Alan R, Eppens, Daniel, Erickson, Catherine, Farhi, Edward, Foxen, Brooks, Giustina, Marissa, Greene, Ami, Gross, Jonathan A, Harrigan, Matthew P, Harrington, Sean D, Hilton, Jeremy, Ho, Alan, Huang, Trent, Huggins, William J, Ioffe, LB, Isakov, Sergei V, Jeffrey, Evan, Jiang, Zhang, Kechedzhi, Kostyantyn, Kim, Seon, Kitaev, Alexei, Kostritsa, Fedor, Landhuis, David, Laptev, Pavel, Lucero, Erik, Martin, Orion, McClean, Jarrod R, McCourt, Trevor, Mi, Xiao, Miao, Kevin C, Mohseni, Masoud, Montazeri, Shirin, Mruczkiewicz, Wojciech, Mutus, Josh, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Newman, Michael, Niu, Murphy Yuezhen, O'Brien, Thomas E, Opremcak, Alex, Ostby, Eric, Pato, Balint, Redd, Nicholas, Roushan, Pedram, Rubin, Nicholas C, Shvarts, Vladimir, Strain, Doug, Szalay, Marco, Trevithick, Matthew D, Villalonga, Benjamin, White, Theodore, Yao, Z Jamie, Yeh, Ping, Yoo, Juhwan, Zalcman, Adam, Neven, Hartmut, Boixo, Sergio, Smelyanskiy, Vadim, Chen, Yu, Megrant, Anthony, and Kelly, Julian
Subjects: Google Quantum AI, General Science & Technology
Abstract: Realizing the potential of quantum computing requires sufficiently low logical error rates1. Many applications call for error rates as low as 10-15 (refs. 2-9), but state-of-the-art quantum platforms typically have physical error rates near 10-3 (refs. 10-14). Quantum error correction15-17 promises to bridge this divide by distributing quantum logical information across many physical qubits in such a way that errors can be detected and corrected. Errors on the encoded logical qubit state can be exponentially suppressed as the number of physical qubits grows, provided that the physical error rates are below a certain threshold and stable over the course of a computation. Here we implement one-dimensional repetition codes embedded in a two-dimensional grid of superconducting qubits that demonstrate exponential suppression of bit-flip or phase-flip errors, reducing logical error per round more than 100-fold when increasing the number of qubits from 5 to 21. Crucially, this error suppression is stable over 50 rounds of error correction. We also introduce a method for analysing error correlations with high precision, allowing us to characterize error locality while performing quantum error correction. Finally, we perform error detection with a small logical qubit using the 2D surface code on the same device18,19 and show that the results from both one- and two-dimensional codes agree with numerical simulations that use a simple depolarizing error model. These experimental demonstrations provide a foundation for building a scalable fault-tolerant quantum computer with superconducting qubits.
Published: 2021

23. Supplementary information for 'Quantum supremacy using a programmable superconducting processor'

Author: Arute, Frank, Arya, Kunal, Babbush, Ryan, Bacon, Dave, Bardin, Joseph C., Barends, Rami, Biswas, Rupak, Boixo, Sergio, Brandao, Fernando G. S. L., Buell, David A., Burkett, Brian, Chen, Yu, Chen, Zijun, Chiaro, Ben, Collins, Roberto, Courtney, William, Dunsworth, Andrew, Farhi, Edward, Foxen, Brooks, Fowler, Austin, Gidney, Craig, Giustina, Marissa, Graff, Rob, Guerin, Keith, Habegger, Steve, Harrigan, Matthew P., Hartmann, Michael J., Ho, Alan, Hoffmann, Markus R., Huang, Trent, Humble, Travis S., Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Kafri, Dvir, Kechedzhi, Kostyantyn, Kelly, Julian, Klimov, Paul V., Knysh, Sergey, Korotkov, Alexander N., Kostritsa, Fedor, Landhuis, David, Lindmark, Mike, Lucero, Erik, Lyakh, Dmitry, Mandra, Salvatore, McClean, Jarrod R., McEwen, Matt, Megrant, Anthony, Mi, Xiao, Michielsen, Kristel, Mohseni, Masoud, Mutus, Josh, Naaman, Ofer, Neeley, Matthew, Neill, Charles, Niu, Murphy Yuezhen, Ostby, Eric, Petukhov, Andre, Platt, John C., Quintana, Chris, Rieffel, Eleanor G., Roushan, Pedram, Rubin, Nicholas C., Sank, Daniel, Satzinger, Kevin J., Smelyanskiy, Vadim, Sung, Kevin J., Trevithick, Matthew D., Vainsencher, Amit, Villalonga, Benjamin, White, Theodore, Yao, Z. Jamie, Yeh, Ping, Zalcman, Adam, Neven, Hartmut, and Martinis, John M.
Subjects: Quantum Physics
Abstract: This is an updated version of supplementary information to accompany "Quantum supremacy using a programmable superconducting processor", an article published in the October 24, 2019 issue of Nature. The main article is freely available at https://www.nature.com/articles/s41586-019-1666-5. Summary of changes since arXiv:1910.11333v1 (submitted 23 Oct 2019): added URL for qFlex source code; added Erratum section; added Figure S41 comparing statistical and total uncertainty for log and linear XEB; new References [1,65]; miscellaneous updates for clarity and style consistency; miscellaneous typographical and formatting corrections., Comment: 67 pages, 51 figures
Published: 2019
Full Text: View/download PDF

24. Candida auris detected in the oral cavity of a dog in Kansas

Author: White, Theodore C., primary, Esquivel, Brooke D., additional, Rouse Salcido, Elisa M., additional, Schweiker, Allison M., additional, dos Santos, Amanda R., additional, Gade, Lalitha, additional, Petro, Erin, additional, KuKanich, Butch, additional, and KuKanich, Kate S., additional
Published: 2024
Full Text: View/download PDF

25. Fabrication and Characterization of Aluminum Airbridges for Superconducting Microwave Circuits

Author: Chen, Zijun, Megrant, Anthony, Kelly, Julian, Barends, Rami, Bochmann, Joerg, Chen, Yu, Chiaro, Ben, Dunsworth, Andrew, Jeffrey, Evan, Mutus, Joshua, O'Malley, Peter, Neill, Charles, Roushan, Pedram, Sank, Daniel, Vainsencher, Amit, Wenner, James, White, Theodore, Cleland, Andrew, and Martinis, John
Subjects: Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Superconductivity
Abstract: Superconducting microwave circuits based on coplanar waveguides (CPW) are susceptible to parasitic slotline modes which can lead to loss and decoherence. We motivate the use of superconducting airbridges as a reliable method for preventing the propagation of these modes. We describe the fabrication of these airbridges on superconducting resonators, which we use to measure the loss due to placing airbridges over CPW lines. We find that the additional loss at single photon levels is small, and decreases at higher drive powers., Comment: 8 pages and 7 figures including supplementary information
Published: 2013
Full Text: View/download PDF

26. Sputtered TiN films for superconducting coplanar waveguide resonators

Author: Ohya, Shinobu, Chiaro, Ben, Megrant, Anthony, Neill, Charles, Barends, Rami, Chen, Yu, Kelly, Julian, Low, David, Mutus, Josh, O'Malley, Peter, Roushan, Pedram, Sank, Daniel, Vainsencher, Amit, Wenner, James, White, Theodore C., Yin, Yi, Schultz, B. D., Palmstrøm, Chris J, Mazin, Benjamin A., Cleland, Andrew N., and Martinis, John M.
Subjects: Condensed Matter - Superconductivity
Abstract: We present a systematic study of the properties of TiN films by varying the deposition conditions in an ultra-high-vacuum reactive magnetron sputtering chamber. By increasing the deposition pressure from 2 to 9 mTorr while keeping a nearly stoichiometric composition of Ti(1-x)N(x) (x=0.5), the film resistivity increases, the dominant crystal orientation changes from (100) to (111), grain boundaries become clearer, and the strong compressive strain changes to weak tensile strain. The TiN films absorb a high concentration of contaminants including hydrogen, carbon, and oxygen when they are exposed to air after deposition. With the target-substrate distance set to 88 mm the contaminant levels increase from ~0.1% to ~10% as the pressure is increased from 2 to 9 mTorr. The contaminant concentrations also correlate with in-plane distance from the center of the substrate and increase by roughly two orders of magnitude as the target-substrate distance is increased from 88 mm to 266 mm. These contaminants are found to strongly influence the properties of TiN films. For instance, the resistivity of stoichiometric films increases by around a factor of 5 as the oxygen content increases from 0.1% to 11%. These results suggest that the sputtered TiN particle energy is critical in determining the TiN film properties, and that it is important to control this energy to obtain high-quality TiN films. Superconducting coplanar waveguide resonators made from a series of nearly stoichiometric films grown at pressures from 2 mTorr to 7 mTorr show an increase in intrinsic quality factor from ~10^4 to ~10^6 as the magnitude of the compressive strain decreases from nearly 3800 MPa to approximately 150 MPa and the oxygen content increases from 0.1% to 8%. The films with a higher oxygen content exhibit lower loss, but the nonuniformity of the oxygen incorporation hinders the use of sputtered TiN in larger circuits., Comment: 9 pages, 9 figures
Published: 2013

27. Sustaining JOINT OPERATIONS: Expanding Posture and Competition by Leveraging the Sustainment Warfighting Function

Author: LaCamera, Paul J. and White, Theodore O.
Subjects: United States. Army, Global economy -- Military aspects, General interest, Military and naval science
Abstract: The National Defense Strategy (NDS) guides us as we enhance our readiness, strengthen alliances and partnerships, and reform to align our resources with our highest priorities. The Pacific remains the [...]
Published: 2021

28. WATER CRAFT Sustainment: Navigating the Indo-Pacific to Strengthen the Force

Author: Graham, Josiah R. and White, Theodore O.
Subjects: United States. Army, United States. Navy, Military personnel -- Training, General interest, Military and naval science
Abstract: On Nov. 19, 2020, USAV LTG William B. Bunker (LSV-4) returned to Joint Base Pearl Harbor-Hickam (JBPHH), Hawaii after completing 94 days of continuous operations at sea and culminating 20,000 [...]
Published: 2021

29. Fungal diversity and drug susceptibility of the oral mycobiome of domestic dogs

Author: Esquivel, Brooke D., primary, Rouse Salcido, Elisa M., additional, Schweiker, Allison M., additional, Holder, Brandon L., additional, KuKanich, Butch, additional, KuKanich, Kate S., additional, and White, Theodore C., additional
Published: 2023
Full Text: View/download PDF

30. Pharmacokinetics of posaconazole within epithelial cells and fungi: insights into potential mechanisms of action during treatment and prophylaxis.

Author: Campoli, Paolo, Perlin, David, Kristof, Arnold, White, Theodore, Sheppard, Donald, and Filler, Scott
Subjects: Aspergillus, endoplasmic reticulum, epithelial cells, hydrophobin rodA, localization, pharmacokinetics, posaconazole, postantifungal effect, Antibiotic Prophylaxis, Antifungal Agents, Aspergillus fumigatus, Biological Transport, Cell Line, Cell Membrane, Epithelial Cells, Fungi, Humans, Mycoses, Protein Binding, Spores, Fungal, Triazoles
Abstract: BACKGROUND: The antifungal posaconazole concentrates within host cells and protects against Aspergillus fumigatus. The specific subcellular location of posaconazole and the mechanism by which cell-associated posaconazole inhibits fungal growth remain uncharacterized. METHODS: Posaconazole was conjugated with the fluorophore boron-dipyrromethene (BDP-PCZ). A549 pulmonary epithelial cells and A. fumigatus were exposed to BDP-PCZ individually and in coculture. BDP-PCZ subcellular localization and trafficking were observed using confocal microscopy and flow cytometry. RESULTS: BDP-PCZ concentrated within A549 cell membranes, and in particular within the endoplasmic reticulum. Epithelial cell-associated BDP-PCZ rapidly transferred to and concentrated within A. fumigatus cell membranes on contact. BDP-PCZ transfer to conidia did not require phagocytosis and was markedly enhanced by the conidial hydrophobin RodA. Within AF, BDP-PCZ also concentrated in membranes including the endoplasmic reticulum and colocalized with the azole target enzyme CYP51a. Concentration of BDP-PCZ within host and fungal cell membranes persisted for >48 hours and could be competitively inhibited by posaconazole but not voriconazole. CONCLUSIONS: Posaconazole concentrates within host cell membranes and rapidly transfers to A. fumigatus, where it accumulates to high concentrations and persists at the site of its target enzyme. These intracellular and intercellular pharmacokinetic properties probably contribute to the efficacy of PCZ.
Published: 2013

31. Inositol Phosphoryl Transferase, Ipt1, Is a Critical Determinant of Azole Resistance and Virulence Phenotypes in Candida glabrata

Author: Shahi, Garima, primary, Kumar, Mohit, additional, Khandelwal, Nitesh Kumar, additional, Banerjee, Atanu, additional, Sarkar, Parijat, additional, Kumari, Sonam, additional, Esquivel, Brooke D., additional, Chauhan, Neeraj, additional, Chattopadhyay, Amitabha, additional, White, Theodore C., additional, Gaur, Naseem A., additional, Singh, Ashutosh, additional, and Prasad, Rajendra, additional
Published: 2022
Full Text: View/download PDF

32. The Making of the President 1972

Author: Geismar, Thomas H., White, Theodore H., Geismar, Thomas H., and White, Theodore H.
Published: 2022

33. Unmasking of CgYor1-Dependent Azole Resistance Mediated by Target of Rapamycin (TOR) and Calcineurin Signaling in Candida glabrata

Author: Kumari, Sonam, primary, Kumar, Mohit, additional, Esquivel, Brooke D., additional, Wasi, Mohd, additional, Pandey, Ajay Kumar, additional, Kumar Khandelwal, Nitesh, additional, Mondal, Alok K., additional, White, Theodore C., additional, Prasad, Rajendra, additional, and Gaur, Naseem A., additional
Published: 2022
Full Text: View/download PDF

34. Azole uptake in Candida auris is strongly correlated with drug resistance

Author: Esquivel, Brooke, primary and White, Theodore C., additional
Published: 2021
Full Text: View/download PDF

35. Preserving entanglement during weak measurement demonstrated with a violation of the Bell-Leggett-Garg inequality

Author: White, Theodore
Subjects: Physics, Amplifiers, Condensed Matter, Quantum, Superconductivity
Abstract: Quantum mechanics makes many predictions, such as superposition, projective measurement, and entanglement, which defy classical intuition. For many years it remained unclear if these predictions were real physical phenomena, or the result of an incomplete understanding of hidden classical variables. For quantum entanglement, the Bell inequality provided the first experimental bound on such hidden variable theories by considering correlated measurements between spatially separated photons. Following a similar logic, the Leggett-Garg inequality provides an experimental test of projective measurement by correlating sequential measurements of the same object. More recently, these inequalities have become important benchmarks for the ``quantumness'' of novel systems, measurement techniques, or methods of generating entanglement. In this work we describe a continuous and controlled exchange of extracted state information and two-qubit entanglement collapse, demonstrated using the hybrid Bell-Leggett-Garg inequality. This effect is quantified by correlating weak measurement results with subsequent projective readout to collect all the statistics of a Bell inequality experiment in a single quantum circuit. This result was made possible by technological advances in superconducting quantum processors which allow precise control and measurement in multi-qubit systems. Additionally we discuss the central role of superconducting Josephson parametric amplifiers, which are a requirement for high fidelity single shot qubit readout. We demonstrate the ability to measure average Bell state information with minimal entanglement collapse, by violating this hybrid Bell-Leggett-Garg inequality at the weakest measurement strengths. This result indicates that it is possible to learn about the dynamics of large entangled systems without significantly affecting their evolution.
Published: 2015

36. Time-crystalline eigenstate order on a quantum processor

Author: Mi, Xiao, primary, Ippoliti, Matteo, additional, Quintana, Chris, additional, Greene, Ami, additional, Chen, Zijun, additional, Gross, Jonathan, additional, Arute, Frank, additional, Arya, Kunal, additional, Atalaya, Juan, additional, Babbush, Ryan, additional, Bardin, Joseph C., additional, Basso, Joao, additional, Bengtsson, Andreas, additional, Bilmes, Alexander, additional, Bourassa, Alexandre, additional, Brill, Leon, additional, Broughton, Michael, additional, Buckley, Bob B., additional, Buell, David A., additional, Burkett, Brian, additional, Bushnell, Nicholas, additional, Chiaro, Benjamin, additional, Collins, Roberto, additional, Courtney, William, additional, Debroy, Dripto, additional, Demura, Sean, additional, Derk, Alan R., additional, Dunsworth, Andrew, additional, Eppens, Daniel, additional, Erickson, Catherine, additional, Farhi, Edward, additional, Fowler, Austin G., additional, Foxen, Brooks, additional, Gidney, Craig, additional, Giustina, Marissa, additional, Harrigan, Matthew P., additional, Harrington, Sean D., additional, Hilton, Jeremy, additional, Ho, Alan, additional, Hong, Sabrina, additional, Huang, Trent, additional, Huff, Ashley, additional, Huggins, William J., additional, Ioffe, L. B., additional, Isakov, Sergei V., additional, Iveland, Justin, additional, Jeffrey, Evan, additional, Jiang, Zhang, additional, Jones, Cody, additional, Kafri, Dvir, additional, Khattar, Tanuj, additional, Kim, Seon, additional, Kitaev, Alexei, additional, Klimov, Paul V., additional, Korotkov, Alexander N., additional, Kostritsa, Fedor, additional, Landhuis, David, additional, Laptev, Pavel, additional, Lee, Joonho, additional, Lee, Kenny, additional, Locharla, Aditya, additional, Lucero, Erik, additional, Martin, Orion, additional, McClean, Jarrod R., additional, McCourt, Trevor, additional, McEwen, Matt, additional, Miao, Kevin C., additional, Mohseni, Masoud, additional, Montazeri, Shirin, additional, Mruczkiewicz, Wojciech, additional, Naaman, Ofer, additional, Neeley, Matthew, additional, Neill, Charles, additional, Newman, Michael, additional, Niu, Murphy Yuezhen, additional, O’Brien, Thomas E., additional, Opremcak, Alex, additional, Ostby, Eric, additional, Pato, Balint, additional, Petukhov, Andre, additional, Rubin, Nicholas C., additional, Sank, Daniel, additional, Satzinger, Kevin J., additional, Shvarts, Vladimir, additional, Su, Yuan, additional, Strain, Doug, additional, Szalay, Marco, additional, Trevithick, Matthew D., additional, Villalonga, Benjamin, additional, White, Theodore, additional, Yao, Z. Jamie, additional, Yeh, Ping, additional, Yoo, Juhwan, additional, Zalcman, Adam, additional, Neven, Hartmut, additional, Boixo, Sergio, additional, Smelyanskiy, Vadim, additional, Megrant, Anthony, additional, Kelly, Julian, additional, Chen, Yu, additional, Sondhi, S. L., additional, Moessner, Roderich, additional, Kechedzhi, Kostyantyn, additional, Khemani, Vedika, additional, and Roushan, Pedram, additional
Published: 2021
Full Text: View/download PDF

37. Faculty and Administrator Perceptions of Their Environments: Different Views or Different Models of Organization?

Author: Peterson, Marvin W. and White, Theodore H.
Abstract: Using a theoretical model of institutional culture, organizational climate, and faculty motivation, a study examined how faculty (n=1,123) and administrators (n=381) in 10 colleges differed in their perceptions, whether differences were affected by institution type, and to what extent faculty and administrators had different implicit models of their institutions. (Author/MSE)
Published: 1992

38. Candidemia in Allogeneic Blood and Marrow Transplant Recipients: Evolution of Risk Factors after the Adoption of Prophylactic Fluconazole

Author: Marr, Kieren A., Seidel, Kristy, White, Theodore C., and Bowden, Raleigh A.
Published: 2000

39. STUDYING OSTEOLOGICAL MATERIAL

Author: WHITE, THEODORE E.
Published: 1953

40. The Braincase of Camarasaurus lentus (Marsh)

Author: White, Theodore E.
Published: 1958

41. Holotype of Plesiosaurus longirostris Blake and Classification of the Plesiosaurs

Author: White, Theodore E.
Published: 1940

42. Observations on the Butchering Technics of Some Aboriginal Peoples Numbers 7, 8, and 9

Author: White, Theodore E.
Published: 1955
Full Text: View/download PDF

43. The Study of Osteological Materials in the Plains

Author: White, Theodore E.
Published: 1956
Full Text: View/download PDF

44. Observations on the Butchering Technique of Some Aboriginal Peoples No. 2

Author: White, Theodore E.
Published: 1953
Full Text: View/download PDF

45. Observations on the Butchering Technique of Some Aboriginal Peoples Nos. 3, 4, 5, and 6

Author: White, Theodore E.
Published: 1954
Full Text: View/download PDF

46. A New Alligator from the Miocene of Florida

Author: White, Theodore E.
Published: 1942
Full Text: View/download PDF

47. A Preliminary Revision of the Genus Lathyrus in North and Central America

Author: White, Theodore G.
Published: 1894
Full Text: View/download PDF

48. Information scrambling in quantum circuits

Author: Mi, Xiao, Roushan, Pedram, Quintana, Chris, Mandrà, Salvatore, Marshall, Jeffrey, Neill, Charles, Arute, Frank, Arya, Kunal, Atalaya, Juan, Babbush, Ryan, Bardin, Joseph C., Barends, Rami, Basso, Joao, Bengtsson, Andreas, Boixo, Sergio, Bourassa, Alexandre, Broughton, Michael, Buckley, Bob B., Buell, David A., Burkett, Brian, Bushnell, Nicholas, Chen, Zijun, Chiaro, Benjamin, Collins, Roberto, Courtney, William, Demura, Sean, Derk, Alan R., Dunsworth, Andrew, Eppens, Daniel, Erickson, Catherine, Farhi, Edward, Fowler, Austin G., Foxen, Brooks, Gidney, Craig, Giustina, Marissa, Gross, Jonathan A., Harrigan, Matthew P., Harrington, Sean D., Hilton, Jeremy, Ho, Alan, Hong, Sabrina, Huang, Trent, Huggins, William J., Ioffe, L. B., Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Kafri, Dvir, Kelly, Julian, Kim, Seon, Kitaev, Alexei, Klimov, Paul V., Korotkov, Alexander N., Kostritsa, Fedor, Landhuis, David, Laptev, Pavel, Lucero, Erik, Martin, Orion, McClean, Jarrod R., McCourt, Trevor, McEwen, Matt, Megrant, Anthony, Miao, Kevin C., Mohseni, Masoud, Montazeri, Shirin, Mruczkiewicz, Wojciech, Mutus, Josh, Naaman, Ofer, Neeley, Matthew, Newman, Michael, Niu, Murphy Yuezhen, O'Brien, Thomas E., Opremcak, Alex, Ostby, Eric, Pato, Balint, Petukhov, Andre, Redd, Nicholas, Rubin, Nicholas C., Sank, Daniel, Satzinger, Kevin J., Shvarts, Vladimir, Strain, Doug, Szalay, Marco, Trevithick, Matthew D., Villalonga, Benjamin, White, Theodore, Yao, Z. Jamie, Yeh, Ping, Zalcman, Adam, Neven, Hartmut, Aleiner, Igor, Kechedzhi, Kostyantyn, Smelyanskiy, Vadim, Chen, Yu, Mi, Xiao, Roushan, Pedram, Quintana, Chris, Mandrà, Salvatore, Marshall, Jeffrey, Neill, Charles, Arute, Frank, Arya, Kunal, Atalaya, Juan, Babbush, Ryan, Bardin, Joseph C., Barends, Rami, Basso, Joao, Bengtsson, Andreas, Boixo, Sergio, Bourassa, Alexandre, Broughton, Michael, Buckley, Bob B., Buell, David A., Burkett, Brian, Bushnell, Nicholas, Chen, Zijun, Chiaro, Benjamin, Collins, Roberto, Courtney, William, Demura, Sean, Derk, Alan R., Dunsworth, Andrew, Eppens, Daniel, Erickson, Catherine, Farhi, Edward, Fowler, Austin G., Foxen, Brooks, Gidney, Craig, Giustina, Marissa, Gross, Jonathan A., Harrigan, Matthew P., Harrington, Sean D., Hilton, Jeremy, Ho, Alan, Hong, Sabrina, Huang, Trent, Huggins, William J., Ioffe, L. B., Isakov, Sergei V., Jeffrey, Evan, Jiang, Zhang, Jones, Cody, Kafri, Dvir, Kelly, Julian, Kim, Seon, Kitaev, Alexei, Klimov, Paul V., Korotkov, Alexander N., Kostritsa, Fedor, Landhuis, David, Laptev, Pavel, Lucero, Erik, Martin, Orion, McClean, Jarrod R., McCourt, Trevor, McEwen, Matt, Megrant, Anthony, Miao, Kevin C., Mohseni, Masoud, Montazeri, Shirin, Mruczkiewicz, Wojciech, Mutus, Josh, Naaman, Ofer, Neeley, Matthew, Newman, Michael, Niu, Murphy Yuezhen, O'Brien, Thomas E., Opremcak, Alex, Ostby, Eric, Pato, Balint, Petukhov, Andre, Redd, Nicholas, Rubin, Nicholas C., Sank, Daniel, Satzinger, Kevin J., Shvarts, Vladimir, Strain, Doug, Szalay, Marco, Trevithick, Matthew D., Villalonga, Benjamin, White, Theodore, Yao, Z. Jamie, Yeh, Ping, Zalcman, Adam, Neven, Hartmut, Aleiner, Igor, Kechedzhi, Kostyantyn, Smelyanskiy, Vadim, and Chen, Yu
Abstract: Interactions in quantum systems can spread initially localized quantum information into the exponentially many degrees of freedom of the entire system. Understanding this process, known as quantum scrambling, is key to resolving several open questions in physics. Here, by measuring the time-dependent evolution and fluctuation of out-of-time-order correlators, we experimentally investigate the dynamics of quantum scrambling on a 53-qubit quantum processor. We engineer quantum circuits that distinguish operator spreading and operator entanglement, and experimentally observe their respective signatures. We show that whereas operator spreading is captured by an efficient classical model, operator entanglement in idealized circuits requires exponentially scaled computational resources to simulate. These results open the path to studying complex and practically relevant physical observables with near-term quantum processors.
Published: 2021

49. Overexpression of TUF1 restores respiratory growth and fluconazole sensitivity to a Cryptococcus neoformans vad1[DELTA] mutant

Author: Panepinto, John C., Misener, Amanda L., Oliver, Brian G., Hu, Guowu, Park, Yoon Dong, Shin, Soowan, White, Theodore C., and Williamson, Peter R.
Subjects: Cryptococcus -- Physiological aspects, Cryptococcus -- Genetic aspects, Cryptococcus -- Research, Bioenergetics -- Genetic aspects, Bioenergetics -- Research, Energy metabolism -- Genetic aspects, Energy metabolism -- Research, Drug resistance in microorganisms -- Genetic aspects, Drug resistance in microorganisms -- Research, Fluconazole -- Research, Fluconazole -- Physiological aspects, Biological sciences
Abstract: The yeast-like fungus Cryptococcus neoformans favours respiration as a mechanism of energy production, and thus depends heavily on mitochondrial function. Previous studies of a C. neoformans vad1[DELTA] mutant revealed reduced expression of the mitochondrial elongation factor TUF1 and defects in glycerol utilization, consistent with mitochondrial dysfunction. In this study, we found that in trans expression of TUF1 in the vad1[DELTA] mutant suppressed the mitochondrial defects, including growth on respiration-dependent carbon sources and fluconazole resistance, associated with VAD1 deletion. Tetracycline, an inhibitor of mitochondrial translation, was found to confer resistance to fluconazole in the wild-type and vad1[DELTA] mutant, whereas the fluconazole susceptibility of the TUFl-overexpressing strain was unaffected by tetracycline treatment. In the presence of fluconazole, the vad1[DELTA] mutant exhibited increased activation of the global transcriptional regulator Sre1. TUF1 overexpression failed to alter cleavage of Sre1 in response to fluconazole in the vad1[DELTA] mutant, suggesting that TUF1 repression in the vad1[DELTA] mutant is distal to Sre1, or that it occurs through an independent pathway. DOI 10.1099/mic.0.035923-0
Published: 2010

50. Candida albicans UPC2 is transcriptionally induced in response to antifungal drugs and anaerobicity through Upc2p-dependent and -independent mechanisms

Author: Hoot, Samantha J., Oliver, Brian G., and White, Theodore C.
Subjects: Antifungal agents -- Dosage and administration, Antifungal agents -- Genetic aspects, Candida albicans -- Genetic aspects, Genetic regulation -- Research, Biological sciences
Abstract: Many genes in the Candida albicans ergosterol biosynthetic pathway are controlled by the transcriptional activator Upc2p, which is upregulated in the presence of azole drugs and has been suggested to regulate its own transcription by an autoregulatory mechanism. The UPC2 promoter was cloned upstream of a luciferase reporter gene (RLUC). UPC2-RLUC activity was induced in response to ergosterol biosynthesis inhibitors and in response to anaerobicity. Under both conditions, induction correlates with the magnitude of sterol depletion. Azole inducibility in the parental strain was approximately 100-fold, and in a UPC2 homozygous deletion strain was 17-fold, suggesting that, in addition to autoregulation, UPC2 transcription is controlled by a novel, Upc2p-independent mechanism(s). Curiously, basal UPC2-RLUC activity was fivefold higher in the deletion strain, which may be an indirect consequence of the lower sterol level in this strain, or a direct consequence of repression by an autoregulatory mechanism. These results suggest that transcriptional regulation of UPC2 expression is important in the response to antifungal drugs, and that this regulation occurs through Upc2p-dependent as well as novel Upc2p-independent mechanisms.
Published: 2008

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Publication Type

Journal

Region

Database

Publisher

358 results on '"White, Theodore"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources