1. Accurately computing electronic properties of a quantum ring
- Author
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Z. Yao, Alan R. Derk, Kevin J. Satzinger, Sergio Boixo, Andre Petukhov, B. Burkett, Thomas E. O'Brien, Jarrod R. McClean, Pavel Laptev, Doug Strain, Ofer Naaman, David A. Buell, Edward Farhi, Zijun Chen, Matthew Neeley, Ping Yeh, Bob B. Buckley, Masoud Mohseni, Charles Neill, Yu Chen, Andreas Bengtsson, Sabrina Hong, Daniel Eppens, Anthony Megrant, Alan Ho, Matthew D. Trevithick, Eric Ostby, Nicholas Redd, Sergei V. Isakov, Matt McEwen, J. A. Gross, Andrew Dunsworth, Josh Mutus, M. Broughton, Michael Newman, Nicholas C. Rubin, Ted White, Ryan Babbush, Fedor Kostritsa, Roberto Collins, Rami Barends, M. Jacob-Mitos, A. Opremcak, Trevor McCourt, Pedram Roushan, Lev Ioffe, Seon Kim, Hartmut Neven, Kunal Arya, Kevin C. Miao, Marco Szalay, Cody Jones, Sean Demura, Brooks Foxen, Benjamin Villalonga, J. Hilton, Orion Martin, Sean D. Harrington, Frank Arute, Zhang Jiang, Alexander N. Korotkov, Adam Zalcman, Julian Kelly, Austin G. Fowler, Vadim Smelyanskiy, Paul V. Klimov, Kostyantyn Kechedzhi, Igor L. Aleiner, Juan Atalaya, Bálint Pató, Catherine Erickson, Joseph C. Bardin, William Courtney, Murphy Yuezhen Niu, Matthew P. Harrigan, William J. Huggins, Xiao Mi, Marissa Giustina, David Landhuis, J. Campero, Nicholas Bushnell, Chris Quintana, Evan Jeffrey, Benjamin Chiaro, Dvir Kafri, E. Lucero, Vladimir Shvarts, Craig Gidney, Trent Huang, Alexandre Bourassa, Daniel Sank, and Wojciech Mruczkiewicz
- Subjects
Physics ,Quantum Physics ,Multidisciplinary ,Quantum decoherence ,Measure (physics) ,FOS: Physical sciences ,Quantum simulator ,01 natural sciences ,Magnetic flux ,010305 fluids & plasmas ,symbols.namesake ,Fourier transform ,Qubit ,0103 physical sciences ,Quantum metrology ,symbols ,Statistical physics ,Quantum Physics (quant-ph) ,010306 general physics ,Quantum - Abstract
A promising approach to study condensed-matter systems is to simulate them on an engineered quantum platform1–4. However, the accuracy needed to outperform classical methods has not been achieved so far. Here, using 18 superconducting qubits, we provide an experimental blueprint for an accurate condensed-matter simulator and demonstrate how to investigate fundamental electronic properties. We benchmark the underlying method by reconstructing the single-particle band structure of a one-dimensional wire. We demonstrate nearly complete mitigation of decoherence and readout errors, and measure the energy eigenvalues of this wire with an error of approximately 0.01 rad, whereas typical energy scales are of the order of 1 rad. Insight into the fidelity of this algorithm is gained by highlighting the robust properties of a Fourier transform, including the ability to resolve eigenenergies with a statistical uncertainty of 10−4 rad. We also synthesize magnetic flux and disordered local potentials, which are two key tenets of a condensed-matter system. When sweeping the magnetic flux we observe avoided level crossings in the spectrum, providing a detailed fingerprint of the spatial distribution of local disorder. By combining these methods we reconstruct electronic properties of the eigenstates, observing persistent currents and a strong suppression of conductance with added disorder. Our work describes an accurate method for quantum simulation5,6 and paves the way to study new quantum materials with superconducting qubits. As a blueprint for high-precision quantum simulation, an 18-qubit algorithm that consists of more than 1,400 two-qubit gates is demonstrated, and reconstructs the energy eigenvalues of the simulated one-dimensional wire to a precision of 1 per cent.
- Published
- 2020