90 results on '"Fu, L."'
Search Results
2. Representation of Berry Phase by the Trajectories of Majorana Stars.
- Author
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Liu, H. D. and Fu, L. B.
- Subjects
- *
ORIGANUM , *PROTON-proton cycle , *SPACE trajectories , *STARS , *STELLAR oscillations - Abstract
The Majorana's stellar representation, which represents the evolution of a quantum state with the trajectories of the Majorana stars on a Bloch sphere, provides an intuitive way to study a physical system with a high dimensional projective Hilbert space. In this Letter, we study the Berry phase by these stars and their loops on the Bloch sphere. It is shown that the Berry phase of a general spin state can be expressed by an elegant formula with the solid angles of Majorana star loops. Furthermore, these results can be used to a general state with arbitrary dimensions. To demonstrate our theory, we study a two mode interacting boson system. Finally, the relation between stars' correlations and quantum entanglement is discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
3. Recollision Dynamic s and Phase Diagram for Nonsequential Double Ionization with Circularly Polarized Laser Fields.
- Author
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Fu, L. B., Xin, G. G., Ye, D. F., and Liu, J.
- Subjects
- *
PHASE diagrams , *IONIZATION (Atomic physics) , *MAGNESIUM , *POLARIZATION (Nuclear physics) , *ELECTRONS , *COLLISIONS (Nuclear physics) - Abstract
A semiclassical quasistatic model is used to investigate the recollision dynamics in circularly polarized laser fields. A velocity window for recollision to occur is found. Only when the return electron's orbits are irregular does significant double ionization take place. The model reproduces the experimental results for magnesium and explains the apparently conflicting experimental results in terms of an analytical formula that demarcates the phase diagram for the nonsequential double ionization in circularly polarized laser fields. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
4. High-fidelity fast quantum driving in nonlinear systems.
- Author
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Dou, F. Q., Fu, L. B., and Liu, J.
- Subjects
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QUANTUM states , *NONLINEAR systems , *ATOMIC interactions , *SPEED limits , *LINEAR statistical models , *OPTICAL lattices - Abstract
We investigate high-fidelity quantum driving in a nonlinear two-level system and find that nonlinear atomic interaction can break the speed limit of the linear model. We show that repulsive atomic interaction can decrease the minimal time requested for reaching target state even to zero, while attractive atomic interaction tends to increase the minimal time. There exists a critical attractive interaction beyond which the target state cannot be reached with high fidelity. Possible experimental observation of the nonlinear effects using a Bose-Einstein condensate in an accelerating optical lattice is discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
5. Classical-trajectory simulation of accelerating neutral atoms with polarized intense laser pulses.
- Author
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Xia, Q. Z., Fu, L. B., and Liu, J.
- Subjects
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TRAJECTORIES (Mechanics) , *ACCELERATION (Mechanics) , *ATOMS , *POLARIZATION (Nuclear physics) , *LASER pulses , *MONTE Carlo method , *CONDUCTION electrons - Abstract
In the present paper, we perform the classical trajectory Monte Carlo simulation of the complex dynamics of accelerating neutral atoms with linearly or circularly polarized intense laser pulses. Our simulations involve the ion motion as well as the tunneling ionization and the scattering dynamics of valence electron in the combined Coulomb and electromagnetic fields, for both helium (He) and magnesium (Mg). We show that for He atoms, only linearly polarized lasers can effectively accelerate the atoms, while for Mg atoms, we find that both linearly and circularly polarized lasers can successively accelerate the atoms. The underlying mechanism is discussed and the subcycle dynamics of accelerating trajectories is investigated. We have compared our theoretical results with a recent experiment [Eichmann Nature (London) 461, 1261 (2009)]. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
6. Berry phase and quantum entanglement in Majorana's stellar representation.
- Author
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Liu, H. D. and Fu, L. B.
- Subjects
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GEOMETRIC quantum phases , *QUANTUM entanglement , *MAJORANA fermions - Abstract
By presenting the evolution of a quantum state with the trajectories of the Majorana stars on the Bloch sphere, the Majorana's stellar provides an intuitive geometric picture to study a quantum system with high-dimensional Hilbert space. We study the Berry phase and quantum entanglement by distributions and motions of these stars on the Bloch sphere. It is shown that both of these unique characters of quantum state can be perfectly represented by the Majorana stars. The former is expressed by the solid angles of Majorana star loops and the distance between stars. For the latter, the distances between stars are also found to be a tool for measuring and classifying the multiparticle entanglement of a symmetric multiqubit pure state. To demonstrate our theory, we study a typical spin model which is equivalent to an interacting boson model or an interacting multiqubit system. The self-trapping phenomenon within is also discussed via the Majorana stars. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
7. Seebeck Rectification Enabled by Intrinsic Thermoelectrical Coupling in Magnetic Tunneling Junctions.
- Author
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Zhang, Z. H., Gui, Y. S., Fu, L., Fan, X. L., Cao, J. W., Xue, D. S., Freitas, P. P., Houssameddine, D., Hemour, S., Wu, K., and Hu, C. M.
- Subjects
- *
THERMOELECTRICITY , *MAGNETIC fields , *TUNNEL magnetoresistance , *MAGNETIC coupling , *NONLINEAR theories , *MATHEMATICAL models - Abstract
An intrinsic thermoelectric coupling effect in the linear response regime of magnetic tunneling junctions (MTJ) is reported. In the dc response, it leads to a nonlinear correction to Ohm's law. Dynamically, it enables a novel Seebeck rectification and second harmonic generation, which apply for a broad frequency range and can be magnetically controlled. A phenomenological model on the footing of the Onsager reciprocal relation and the principle of energy conservation explains very well the experimental results obtained from both dc and frequency-dependent transport measurements performed up to GHz frequencies. Our work refines previous understanding of magnetotransport and microwave rectification in MTJs. It forms a new foundation for utilizing spin caloritronics in high-frequency applications. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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8. Berry phase and Hannay angle of an interacting boson system.
- Author
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Li, S. C., Liu, J., and Fu, L. B.
- Subjects
- *
GEOMETRIC quantum phases , *ANGLE modulation , *INTERACTING boson models , *MANY-body problem , *COHERENCE (Physics) , *QUANTUM interference , *HARMONIC oscillators - Abstract
In the present paper, we investigate the Berry phase and the Hannay angle of an interacting two-mode boson system and obtain their analytic expressions in explicit forms. The relation between the Berry phase and the Hannay angle is discussed. We find that, in the large-particle-number limit, the classical Hannay angle equals the particle number derivative of the quantum Berry phase except for a sign. This relationship is applicable to other many-body boson systems where the coherent-state description is available and the total particle number is conserved. The measurement of the classical Hannay angle in the many-body systems is briefly discussed as well. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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9. Extended laser filamentation in air generated by femtosecond annular Gaussian beams.
- Author
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Feng, Z. F., Li, W., Yu, C. X., Liu, X., Liu, J., and Fu, L. B.
- Subjects
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GAUSSIAN beams , *FEMTOSECOND lasers , *ARGON plasmas , *LIGHT propagation , *LASER pulses , *FILAMENTATION instability - Abstract
Extending the longitudinal range of plasma channels produced by femtosecond annular (ring) Gaussian beams in atmosphere is numerically investigated. We find that the length of a stable plasma channel induced by the annular Gaussian beam, comparing with a Gaussian beam under the same initial condition, has a significant improvement, which can be well understood from two aspects. The dynamic complementation caused by the optical system composing of an axicon and a diverging lens can extend the plasma channel greatly, and the special initial transverse distribution of ring-Gaussian pulse leads to pulse splitting and redistribution of the pulse energy before the formation of optical filament. The ultrashort ring-Gaussian beam perhaps offers a new and an efficient route towards the generation of extended optical filament. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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10. Attosecond XUV absorption spectroscopy of doubly excited states in helium atoms dressed by a time-delayed femtosecond infrared laser.
- Author
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Yang, Z. Q., Ye, D. F., Ding, Thomas, Pfeifer, Thomas, and Fu, L. B.
- Subjects
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HELIUM atom , *ABSORPTION spectra , *MOLECULAR spectroscopy , *EXCITED states , *FEMTOSECOND lasers , *SCHRODINGER equation , *LASER pulses , *INFRARED lasers - Abstract
In the present paper, we investigate the time-resolved transient absorption spectroscopy of doubly excited states of helium atoms by solving the time-dependent two-electron Schrödinger equation numerically based on a one-dimensional model. The helium atoms are subjected to an extreme ultraviolet (XUV) attosecond pulse and a time-delayed infrared (IR) few-cycle laser pulse. A superposition of doubly excited states populated by the XUV pulse is identified, which interferes with the direct ionization pathway leading to Fano resonance profiles in the photoabsorption spectrum. In the presence of an IR laser, however, the Fano line profiles are strongly modified: A shifting, splitting, and broadening of the original absorption lines is observed when the XUV attosecond pulse and infrared few-cycle laser pulse overlap in time, which is in good agreement with recent experimental results. At certain time delays, we observe symmetric Lorentz, inverted Fano profiles, and even negative absorption cross sections indicating that the XUV light can be amplified during the interaction with atoms. We further prove that the above pictures are general for different doubly excited states by suitably varying the frequency of the IR field to coherently couple the corresponding states. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
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11. Generating Overcritical Dense Relativistic Electron Beams via Self-Matching Resonance Acceleration.
- Author
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Liu, B., Wang, H. Y., Liu, J., Fu, L. B., Xu, Y. J., Yan, X. Q., and He, X. T.
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ELECTRON beams , *PARTICLE beams , *LEPTONS (Nuclear physics) , *POSITRONS , *FIELD theory (Physics) , *MAGNETIC fields - Abstract
We show a novel self-matching resonance acceleration regime for generating dense relativistic electron beams by using ultraintense circularly polarized laser pulses in near-critical density plasmas. When the self-generated quasistatic axial magnetic field is strong enough to pinch and trap thermal relativistic electrons, an overdense electron bunch is formed in the center of the laser channel. In the trapping process, the electron betatron frequencies and phases can be adjusted automatically to match the resonance condition. The matched electrons are accelerated continuously and a collimated electron beam with overcritical density, helical structure, and plateau profile energy spectrum is hence generated. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
12. Observation of a Warped Helical Spin Texture in Bi2Se3 from Circular Dichroism Angle-Resolved Photoemission Spectroscopy.
- Author
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Wang, Y. H., Hsieh, D., Pilon, D., Fu, L., Gardner, D. R., Lee, Y. S., and Gedik, N.
- Subjects
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TOPOLOGY , *SPINTRONICS , *CIRCULAR dichroism , *PHOTOEMISSION , *SPECTRUM analysis , *MATHEMATICAL models - Abstract
A differential coupling of topological surface states to left- versus right-circularly polarized light is the basis of many optospintronics applications of topological insulators. Here we report direct evidence of circular dichroism from the surface states of Bi2Se3 using laser-based time-of-flight angle-resolved photoemission spectroscopy. By employing a novel sample rotational analysis, we resolve unusual modulations in the circular dichroism photoemission pattern as a function of both energy and momentum, which perfectly mimic the predicted but hitherto unobserved three-dimensional warped spin texture of the surface slates. By developing a microscopic theory of photoemission from topological surface states, we show that this correlation is a natural consequence of spin-orbit coupling. These results suggest that our technique may be a powerful probe of the spin texture of spin-orbit coupled materials in general. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
13. Coulomb effects in photon-momentum partitioning during atomic ionization by intense linearly polarized light.
- Author
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Liu, J., Xia, Q. Z., Tao, J. F., and Fu, L. B.
- Subjects
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PHOTONS , *IONIZATION (Atomic physics) , *LINEAR systems , *OPTICAL polarization , *MOMENTUM transfer , *BOUND states - Abstract
Partitioning of photon momenta between the ion and electron in photoionization and the involved subcycle dynamics are investigated using an extended semiclassical model, where momentum transfer from the photon to the electron-ion system via the (magnetic) Lorentz force is taken into account. It is found that in both the tunneling and rescattering processes, Coulomb attraction between the ion and electron plays a role in the momentum partitioning. The effect is especially important for linearly polarized light since the photons that lift the electron out of the bound state do not always contribute to the forward ion momentum. The present results can have important implications in the generation of terahertz radiation and the calibration of tunnel exit by measuring final ion longitudinal momentum. [ABSTRACT FROM AUTHOR]
- Published
- 2013
- Full Text
- View/download PDF
14. Quantum Interference of Glory Rescattering in Strong-Field Atomic Ionization.
- Author
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Xia, Q. Z., Tao, J. F., Cai, J., Fu, L. B., and Liu, J.
- Subjects
- *
QUANTUM interference , *ANGULAR momentum (Mechanics) , *POLARIZATION (Electricity) - Abstract
During the ionization of atoms irradiated by linearly polarized intense laser fields, we find for the first time that the transverse momentum distribution of photoelectrons can be well fitted by a squared zeroth-order Bessel function because of the quantum interference effect of glory rescattering. The characteristic of the Bessel function is determined by the common angular momentum of a number of semiclassical paths termed as glory trajectories, which are launched with different nonzero initial transverse momenta distributed on a specific circle in the momentum plane and finally deflected to the same asymptotic momentum, which is along the polarization direction, through post-tunneling rescattering. Glory rescattering theory based on the semiclassical path-integral formalism is developed to address this effect quantitatively. Our theory can resolve the long-standing discrepancies between existing theories and experiments on the fringe location, predict the sudden transition of the fringe structure in holographic patterns, and shed light on the quantum interference aspects of low-energy structures in strong-field atomic ionization. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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15. Topologically Entangled Rashba-Split Shockley States on the Surface of Grey Arsenic.
- Author
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Peng Zhang, Ma, J.-Z., Ishida, Y., Zhao, L.-X., Xu, Q.-N., Lv, B.-Q., Yaji, K., Chen, G.-F., Weng, H.-M., Dai, X., Fang, Z., Chen, X.-Q., Fu, L., Qian, T., Ding, H., and Shin, S.
- Subjects
- *
ARSENIC , *RASHBA effect , *SURFACE states - Abstract
We discover a pair of spin-polarized surface bands on the (111) face of grey arsenic by using angle-resolved photoemission spectroscopy (ARPES). In the occupied side, the pair resembles typical nearly-free-electron Shockley states observed on noble-metal surfaces. However, pump-probe ARPES reveals that the spin-polarized pair traverses the bulk band gap and that the crossing of the pair at Γ is topologically unavoidable. First-principles calculations well reproduce the bands and their nontrivial topology; the calculations also support that the surface states are of Shockley type because they arise from a band inversion caused by crystal field. The results provide compelling evidence that topological Shockley states are realized on As(111). [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
16. Coulomb rescattering in nondipole interaction of atoms with intense laser fields.
- Author
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Tao, J. F., Xia, Q. Z., Cai, J., Fu, L. B., and Liu, J.
- Subjects
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IONIZATION (Atomic physics) , *DYNAMICS , *SCATTERING (Physics) - Abstract
We investigate the ionization dynamics of atoms irradiated by an intense laser field using a semiclassical model that includes magnetic Lorentz force in the rescattering process. We find that the electrons tunneled with different initial transverse momenta (i.e., perpendicular to the instantaneous electric field direction) distributed on a specific circle in the momentum plane can finally converge to the same transverse momentum after experiencing Coulomb forward scattering. These electron trajectories lead to a bright spot structure in the two-dimensional transverse momentum distribution, and particularly in the long-wavelength limit, a nonzero momentum peak in the direction antiparallel to the laser propagation (or radiation pressure) direction. By analyzing the subcycle dynamics of rescattering trajectories, we unveil the underlying mechanism of the anti-intuitive peak. Beyond the strong-field approximation and the dipole approximation, we quantitatively predict the spot center and the peak position. Our results are compared with a recent experiment and some theoretical predictions are given. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
17. Directional Localization from a Magnetic Field in Moiré Systems.
- Author
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Paul N, Crowley PJD, and Fu L
- Abstract
Moiré materials provide a highly tunable platform in which novel electronic phenomena can emerge. We study strained moiré materials in a uniform magnetic field and predict highly anisotropic electrical conductivity that switches easy axis as magnetic field or strain is varied. The dramatic anisotropy reflects one-dimensional localization (directional localization) of the electron wave functions along a crystal axis due to quantum interference effects. This can be understood in an effective one-dimensional quasiperiodic Aubry-André-Harper-like model, or in a complementary semiclassical picture. This phenomenon should be observable in strained moiré materials at realistic fields and low strain disorder, as well as unstrained systems with anisotropic Fermi surfaces.
- Published
- 2024
- Full Text
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18. Strong-Coupling Phases of Trions and Excitons in Electron-Hole Bilayers at Commensurate Densities.
- Author
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Dai DD and Fu L
- Abstract
We introduce density imbalanced electron-hole bilayers at a commensurate 2:1 density ratio as a platform for realizing novel phases of electrons, excitons, and trions. Through the independently tunable carrier densities and interlayer spacing, competition between kinetic energy, intralayer repulsion, and interlayer attraction yields a rich phase diagram. By a combination of theoretical analysis and numerical calculation, we find a variety of strong-coupling phases in different parameter regions, including quantum crystals of electrons, excitons, and trions. We also propose an "electron-exciton supersolid" phase that features electron crystallization and exciton superfluidity simultaneously. The material realization and experimental signature of these phases are discussed in the context of semiconductor transition metal dichalcogenide bilayers.
- Published
- 2024
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19. Artificial Atoms, Wigner Molecules, and an Emergent Kagome Lattice in Semiconductor Moiré Superlattices.
- Author
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Reddy AP, Devakul T, and Fu L
- Abstract
Semiconductor moiré superlattices comprise an array of artificial atoms and provide a highly tunable platform for exploring novel electronic phases. We introduce a theoretical framework for studying moiré quantum matter that treats intra-moiré-atom interactions exactly and is controlled in the limit of large moiré period. We reveal an abundance of new physics arising from strong electron interactions when there are multiple electrons within a moiré unit cell. In particular, at filling factor n=3, the Coulomb interaction within each three-electron moiré atom leads to a three-lobed "Wigner molecule." When their size is comparable to the moiré period, the Wigner molecules form an emergent Kagome lattice. Our Letter identifies two universal length scales characterizing the kinetic and interaction energies in moiré materials and demonstrates a rich phase diagram due to their interplay.
- Published
- 2023
- Full Text
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20. Zero-Field Composite Fermi Liquid in Twisted Semiconductor Bilayers.
- Author
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Goldman H, Reddy AP, Paul N, and Fu L
- Abstract
Recent experiments have produced evidence for fractional quantum anomalous Hall (FQAH) states at zero magnetic field in the semiconductor moiré superlattice system tMoTe_{2}. Here, we argue that a composite fermion description, already a unifying framework for the phenomenology of 2D electron gases at high magnetic fields, provides a similarly powerful perspective in this new context. To this end, we present exact diagonalization evidence for composite Fermi liquid states at zero magnetic field in tMoTe_{2} at fillings n=1/2 and n=3/4. We dub these non-Fermi liquid metals anomalous composite Fermi liquids (ACFLs), and we argue that they play a central organizing role in the FQAH phase diagram. We proceed to develop a long wavelength theory for this ACFL state that offers concrete experimental predictions upon doping the composite Fermi sea, including a Jain sequence of FQAH states and a new type of commensurability oscillations originating from the superlattice potential intrinsic to the system.
- Published
- 2023
- Full Text
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21. Ubiquitous Superconducting Diode Effect in Superconductor Thin Films.
- Author
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Hou Y, Nichele F, Chi H, Lodesani A, Wu Y, Ritter MF, Haxell DZ, Davydova M, Ilić S, Glezakou-Elbert O, Varambally A, Bergeret FS, Kamra A, Fu L, Lee PA, and Moodera JS
- Abstract
The macroscopic coherence in superconductors supports dissipationless supercurrents that could play a central role in emerging quantum technologies. Accomplishing unequal supercurrents in the forward and backward directions would enable unprecedented functionalities. This nonreciprocity of critical supercurrents is called the superconducting (SC) diode effect. We demonstrate the strong SC diode effect in conventional SC thin films, such as niobium and vanadium, employing external magnetic fields as small as 1 Oe. Interfacing the SC layer with a ferromagnetic semiconductor EuS, we further accomplish the nonvolatile SC diode effect reaching a giant efficiency of 65%. By careful control experiments and theoretical modeling, we demonstrate that the critical supercurrent nonreciprocity in SC thin films could be easily accomplished with asymmetrical vortex edge and surface barriers and the universal Meissner screening current governing the critical currents. Our engineering of the SC diode effect in simple systems opens the door for novel technologies while revealing the ubiquity of the Meissner screening effect induced SC diode effect in superconducting films, and it should be eliminated with great care in the search for exotic superconducting states harboring finite-momentum Cooper pairing.
- Published
- 2023
- Full Text
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22. Quantum Computing with Majorana Kramers Pairs.
- Author
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Schrade C and Fu L
- Subjects
- Magnetic Fields, Computing Methodologies, Quantum Theory
- Abstract
We propose a universal gate set acting on a qubit formed by the degenerate ground states of a Coulomb-blockaded time-reversal invariant topological superconductor island with spatially separated Majorana Kramers pairs: the "Majorana Kramers qubit." All gate operations are implemented by coupling the Majorana Kramers pairs to conventional superconducting leads. Interestingly, in such an all-superconducting device, the energy gap of the leads provides another layer of protection from quasiparticle poisoning independent of the island charging energy. Moreover, the absence of strong magnetic fields-which typically reduce the superconducting gap size of the island-suggests a unique robustness of our qubit to quasiparticle poisoning due to thermal excitations. Consequently, the Majorana Kramers qubit should benefit from prolonged coherence times and may provide an alternative route to a Majorana-based quantum computer.
- Published
- 2022
- Full Text
- View/download PDF
23. Sound attenuation in two-dimensional glasses at finite temperatures.
- Author
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Fu L and Wang L
- Abstract
The thermal conductivity of glasses exhibits an unusual temperature dependence compared to their crystalline counterparts. Sound attenuation due to disorder in glasses was proposed to be important in rationalizing this special behavior. Simulation studies suggest that in the harmonic approximation, the sound attenuation follows Rayleigh scattering scaling at small wave vector in both two-dimensional (2D) and 3D glasses. The influence of the anharmonicity on sound attenuation has very recently been investigated numerically, but only in 3D glasses. Hence, it remains unknown in simulations how sound attenuation changes with the wave vector in 2D glasses when the anharmonicity comes into play. Here, we address this issue by performing computer simulations in low-temperature 2D glasses over a large range of glass stabilities. We find that the way the anharmonicity affects sound attenuation in 2D glasses is the same as that in 3D, thus revealing that numerically the influence of the anharmonicity on sound attenuation does not rely on the spatial dimension.
- Published
- 2022
- Full Text
- View/download PDF
24. Moiré Landau Fans and Magic Zeros.
- Author
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Paul N, Crowley PJD, Devakul T, and Fu L
- Abstract
We study the energy spectrum of moiré systems under a uniform magnetic field. The superlattice potential generally broadens Landau levels into Chern bands with finite bandwidth. However, we find that these Chern bands become flat at a discrete set of magnetic fields which we dub "magic zeros." The flat band subspace is generally different from the Landau level subspace in the absence of the moiré superlattice. By developing a semiclassical quantization method and taking account of superlattice induced Bragg reflection, we prove that magic zeros arise from the simultaneous quantization of two distinct k-space orbits. For instance, we show the chiral model of TBG has flat bands at special fields for any twist angle in the nth Landau level for |n|>1. The flat bands at magic zeros provide a new setting for exploring crystalline fractional quantum Hall physics.
- Published
- 2022
- Full Text
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25. Tunable Magnonic Chern Bands and Chiral Spin Currents in Magnetic Multilayers.
- Author
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Hu Z, Fu L, and Liu L
- Abstract
Realization of novel topological phases in magnonic band structures represents a new opportunity for the development of spintronics and magnonics with low power consumption. In this work, we show that in antiparallelly aligned magnetic multilayers, the long-range, chiral dipolar interaction between propagating magnons generates bulk bands with nonzero Chern integers and magnonic surface states carrying chiral spin currents. The surface states are highly localized and can be easily toggled between nontrivial and trivial phases through an external magnetic field. The realization of chiral surface spin currents in this dipolarly coupled heterostructure represents a magnonic implementation of the coupled wire model that has been extensively explored in electronic systems. Our work presents an easy-to-implement system for realizing topological magnonic surface states and low-dissipation spin current transport in a tunable manner.
- Published
- 2022
- Full Text
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26. Direct Atomic-Scale Observation of Ultrasmall Ag Nanowires that Exhibit fcc, bcc, and hcp Structures under Bending.
- Author
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Sun S, Li D, Yang C, Fu L, Kong D, Lu Y, Guo Y, Liu D, Guan P, Zhang Z, Chen J, Ming W, Wang L, and Han X
- Abstract
Metals usually have three crystal structures: face-centered cubic (fcc), body-centered cubic (bcc), and hexagonal-close packed (hcp) structures. Typically, metals exhibit only one of these structures at room temperature. Mechanical processing can cause phase transition in metals, however, metals that exhibit all the three crystal structures have rarely been approached, even when hydrostatic pressure or shock conditions are applied. Here, through in situ observation of the atomic-scale bending and tensile process of ∼5 nm-sized Ag nanowires (NWs), we show that bending is an effective method to facilitate fcc-structured Ag to access all the above-mentioned structures. The process of transitioning the fcc structure into a bcc structure, then into an hcp structure, and finally into a re-oriented fcc structure under bending has been witnessed in its entirety. This re-oriented fcc structure is twin-related to the matrix, which leads to twin nucleation without the need for partial dislocation activities. The results of this study advance our understanding of the deformation mechanism of small-sized fcc metals.
- Published
- 2022
- Full Text
- View/download PDF
27. Quantum Phases in a Quantum Rabi Triangle.
- Author
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Zhang YY, Hu ZX, Fu L, Luo HG, Pu H, and Zhang XF
- Abstract
The interplay of interactions, symmetries, and gauge fields usually leads to intriguing quantum many-body phases. To explore the nature of emerging phases, we study a quantum Rabi triangle system as an elementary building block for synthesizing an artificial magnetic field. We develop an analytical approach to study the rich phase diagram and the associated quantum criticality. Of particular interest is the emergence of a chiral-coherent phase, which breaks both the Z_{2} and the chiral symmetry. In this chiral phase, photons flow unidirectionally and the chirality can be tuned by the artificial gauge field, exhibiting a signature of broken time-reversal symmetry. The finite-frequency scaling analysis further confirms the associated phase transition to be in the universality class of the Dicke model. This model can simulate a broad range of physical phenomena of light-matter coupling systems, and may have an application in future developments of various quantum information technologies.
- Published
- 2021
- Full Text
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28. Charge-4e Superconductivity from Multicomponent Nematic Pairing: Application to Twisted Bilayer Graphene.
- Author
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Fernandes RM and Fu L
- Abstract
We show that unconventional nematic superconductors with multicomponent order parameter in lattices with three- and sixfold rotational symmetries support a charge-4e vestigial superconducting phase above T_{c}. The charge-4e state, which is a condensate of four-electron bound states that preserve the rotational symmetry of the lattice, is nearly degenerate with a competing vestigial nematic state, which is nonsuperconducting and breaks the rotational symmetry. This robust result is the consequence of a hidden discrete symmetry in the Ginzburg-Landau theory, which permutes quantities in the gauge sector and in the crystalline sector of the symmetry group. We argue that random strain generally favors the charge-4e state over the nematic phase, as it acts as a random mass to the former but as a random field to the latter. Thus, we propose that two-dimensional inhomogeneous systems displaying nematic superconductivity, such as twisted bilayer graphene, provide a promising platform to realize the elusive charge-4e superconducting phase.
- Published
- 2021
- Full Text
- View/download PDF
29. DMFT Reveals the Non-Hermitian Topology and Fermi Arcs in Heavy-Fermion Systems.
- Author
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Nagai Y, Qi Y, Isobe H, Kozii V, and Fu L
- Abstract
When a strongly correlated system supports well-defined quasiparticles, it allows for an elegant one-body effective description within the non-Hermitian topological theory. While the microscopic many-body Hamiltonian of a closed system remains Hermitian, the one-body quasiparticle Hamiltonian is non-Hermitian due to the finite quasiparticle lifetime. We use such a non-Hermitian description in the heavy-fermion two-dimensional systems with the momentum-dependent hybridization to reveal a fascinating phenomenon which can be directly probed by the spectroscopic measurements, the bulk "Fermi arcs." Starting from a simple two-band model, we first combine the phenomenological approach with the perturbation theory to show the existence of the Fermi arcs and reveal their connection to the topological exceptional points, special points in the Brillouin zone where the Hamiltonian is nondiagonalizable. The appearance of such points necessarily requires that the electrons belonging to different orbitals have different lifetimes. This requirement is naturally satisfied in the heavy-fermion systems, where the itinerant c electrons experience much weaker interaction than the localized f electrons. We then utilize the dynamical mean field theory to numerically calculate the spectral function and confirm our findings. We show that the concept of the exceptional points in the non-Hermitian quasiparticle Hamiltonians is a powerful tool for predicting new phenomena in strongly correlated electron systems.
- Published
- 2020
- Full Text
- View/download PDF
30. Multiple In-Gap States Induced by Topological Surface States in the Superconducting Topological Crystalline Insulator Heterostructure Sn_{1-x}Pb_{x}Te-Pb.
- Author
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Yang H, Li YY, Liu TT, Guan DD, Wang SY, Zheng H, Liu C, Fu L, and Jia JF
- Abstract
Superconducting topological crystalline insulators (TCIs) have been proposed to be a new type of topological superconductor where multiple Majorana zero modes may coexist under the protection of lattice symmetries. The bulk superconductivity of TCIs has been realized, but it is quite challenging to detect the superconductivity of topological surface states inside their bulk superconducting gaps. Here, we report high-resolution scanning tunneling spectroscopy measurements on lateral Sn_{1-x}Pb_{x}Te-Pb heterostructures using superconducting tips. Both the bulk superconducting gap and the multiple in-gap states with energy differences of ∼0.3 meV can be clearly resolved on TCI Sn_{1-x}Pb_{x}Te at 0.38 K. Quasiparticle interference measurements further confirm the in-gap states are gapless. Our work demonstrates that the unique topological superconductivity of a TCI can be directly distinguished in the density of states, which helps to further investigate the multiple Dirac and Majorana fermions inside the superconducting gap.
- Published
- 2020
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31. Liquid-Solid Slip on Charged Walls: The Dramatic Impact of Charge Distribution.
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Xie Y, Fu L, Niehaus T, and Joly L
- Abstract
Nanofluidic systems show great promise for applications in energy conversion, where their performance can be enhanced by nanoscale liquid-solid slip. However, efficiency is also controlled by surface charge, which is known to reduce slip. Combining molecular dynamics simulations and analytical developments, we show the dramatic impact of surface charge distribution on the slip-charge coupling. Homogeneously charged graphene exhibits a very favorable slip-charge relation (rationalized with a new theoretical model correcting some weaknesses of the existing ones), leading to giant electrokinetic energy conversion. In contrast, slip is strongly affected on heterogeneously charged surfaces, due to the viscous drag induced by counterions trapped on the surface. In that case slip should depend on the detailed physical chemistry of the interface controlling the fraction of bound ions. Our numerical results and theoretical models provide new fundamental insight into the molecular mechanisms of liquid-solid slip, and practical guidelines for searching new functional interfaces with optimal energy conversion properties, e.g., for blue energy or waste heat harvesting.
- Published
- 2020
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32. Magnus Hall Effect.
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Papaj M and Fu L
- Abstract
A new type of a linear response Hall effect is predicted in time-reversal-invariant systems with a built-in electric field at zero magnetic field. The Hall response results from a quantum Magnus effect where a self-rotating Bloch electron wave packet moving under an electric field develops an anomalous velocity in the transverse direction. We show that in the ballistic limit the Magnus Hall conductance measures the distribution of the Berry curvature on the Fermi surface.
- Published
- 2019
- Full Text
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33. Giant Thermoelectric Response of Nanofluidic Systems Driven by Water Excess Enthalpy.
- Author
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Fu L, Joly L, and Merabia S
- Abstract
Nanofluidic systems could in principle be used to produce electricity from waste heat, but current theoretical descriptions predict a rather poor performance as compared to thermoelectric solid materials. Here we investigate the thermoelectric response of NaCl and NaI solutions confined between charged walls, using molecular dynamics simulations. We compute a giant thermoelectric response, 2 orders of magnitude larger than the predictions of standard models. We show that water excess enthalpy-neglected in the standard picture-plays a dominant role in combination with the electro-osmotic mobility of the liquid-solid interface. Accordingly, the thermoelectric response can be boosted using surfaces with large hydrodynamic slip. Overall, the heat harvesting performance of the model systems considered here is comparable to that of the best thermoelectric materials, and the fundamental insight provided by molecular dynamics suggests guidelines to further optimize the performance, opening the way to recycle waste heat using nanofluidic devices.
- Published
- 2019
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34. Spin-Orbital Density Wave and a Mott Insulator in a Two-Orbital Hubbard Model on a Honeycomb Lattice.
- Author
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Zhu Z, Sheng DN, and Fu L
- Abstract
Inspired by the recent discovery of correlated insulating states in twisted bilayer graphene, we study a two-orbital Hubbard model on the honeycomb lattice with two electrons per unit cell. Based on the real-space density matrix renormalization group simulation, we identify a metal-insulator transition around U_{c}/t=2.5-3. In the vicinity of U_{c}, we find strong spin-orbital density wave fluctuations at commensurate wave vectors, accompanied by weaker incommensurate charge density wave fluctuations. The spin-orbital density wave fluctuations are enhanced with increasing system sizes, suggesting the possible emergence of long-range order in the two-dimensional limit. At larger U, our calculations indicate a possible nonmagnetic Mott insulator phase without spin or orbital polarization. Our findings offer new insight into correlated electron phenomena in twisted bilayer graphene and other multiorbital honeycomb materials.
- Published
- 2019
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35. Multichannel Interference in Resonancelike Enhancement of High-Order Above-Threshold Ionization.
- Author
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Xu L and Fu L
- Abstract
The intensity-dependent resonancelike enhancement phenomenon in the high-order above-threshold ionization spectrum is a typical quantum effect for atoms or molecules in an intense laser field, which has not been well understood. The calculations of the time-dependent Schrödinger equation (TDSE) are in remarkable agreement with the experimental data, but they cannot clarify the contributions of the bound states. The semiclassical approach of strong field approximation, in which no excited states are involved, can obtain a similar phenomenon, but the laser intensities of enhanced regions predicted by the strong field approximation are inconsistent with the results of the TDSE. In this Letter, a new fully quantum model is established from the TDSE without any excited states. Two types of enhanced structures, unimodal and multimodal structures, are found in the results of the TDSE and model. In addition, the calculations of the model reproduce the key features of the results of the TDSE. It shows that the excited states are not the key factor in the resonancelike enhancements in our calculated system, since there are no excited states in our model. Based on the calculations of our model, we show that such resonancelike enhancements are caused by the constructive interference of different momentum transfer channels. Last, the Fano-like line shapes are also discussed for the features of multichannel interference.
- Published
- 2019
- Full Text
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36. Powerful harmonic charging in a quantum battery.
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Zhang YY, Yang TR, Fu L, and Wang X
- Abstract
We consider a harmonic charging field as an energy charger for the quantum battery, which consists of an ensemble of two-level atoms. The charging of noninteracting atoms is completely fulfilled, which exhibits a substantial improvement over previous static charging fields. Involving the repulsive interactions of atoms, the fully charging is achieved with shorter charged period over the noninteracting case, yielding an advantage for the charging. Excluding the charging field, a quantum phase transition is induced by the attractive atom-atom interactions, and the interacting atoms become degenerate in the ground state. We find that the degenerate states play a negative role in the charging due to the gapless energies. The atoms with strong attractive interactions can not be charged completely, which is accompanied by a drop of the maximum stored energy.
- Published
- 2019
- Full Text
- View/download PDF
37. Glassy, Gardner-like phenomenology in minimally polydisperse crystalline systems.
- Author
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Charbonneau P, Corwin EI, Fu L, Tsekenis G, and van der Naald M
- Abstract
We report on a nonequilibrium phase of matter, the minimally disordered crystal phase, which we find exists between the maximally amorphous glasses and the ideal crystal. Even though these near crystals appear highly ordered, they display glassy and jamming features akin to those observed in amorphous solids. Structurally, they exhibit a power-law scaling in their probability distribution of weak forces and small interparticle gaps as well as a flat density of vibrational states. Dynamically, they display anomalous aging above a characteristic pressure. Quantitatively, this disordered crystal phase has much in common with the Gardner-like phase seen in maximally disordered solids. Near crystals should be amenable to experimental realizations in commercially available particulate systems and are to be indispensable in verifying the theory of amorphous materials.
- Published
- 2019
- Full Text
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38. Majorana Superconducting Qubit.
- Author
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Schrade C and Fu L
- Abstract
We propose a platform for universal quantum computation that uses conventional s-wave superconducting leads to address a topological qubit stored in spatially separated Majorana bound states in a multiterminal topological superconductor island. Both the manipulation and readout of this "Majorana superconducting qubit" are realized by tunnel couplings between Majorana bound states and the superconducting leads. The ability of turning on and off tunnel couplings on demand by local gates enables individual qubit addressability while avoiding cross-talk errors. By combining the scalability of superconducting qubit and the robustness of topological qubits, the Majorana superconducting qubit may provide a promising and realistic route towards quantum computation.
- Published
- 2018
- Full Text
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39. Quantum Oscillation from In-Gap States and a Non-Hermitian Landau Level Problem.
- Author
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Shen H and Fu L
- Abstract
Motivated by recent experiments on Kondo insulators, we theoretically study quantum oscillations from disorder-induced in-gap states in small-gap insulators. By solving a non-Hermitian Landau level problem that incorporates the imaginary part of electron's self-energy, we show that the oscillation period is determined by the Fermi surface area in the absence of the hybridization gap, and we derive an analytical formula for the oscillation amplitude as a function of the indirect band gap, scattering rates, and temperature. Over a wide parameter range, we find that the effective mass is controlled by scattering rates, while the Dingle factor is controlled by the indirect band gap. We also show the important effect of scattering rates in reshaping the quasiparticle dispersion in connection with angle-resolved photoemission measurements on heavy fermion materials.
- Published
- 2018
- Full Text
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40. Parity-Controlled 2π Josephson Effect Mediated by Majorana Kramers Pairs.
- Author
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Schrade C and Fu L
- Abstract
We study a time-reversal-invariant topological superconductor island hosting spatially separated Majorana Kramers pairs, with weak tunnel couplings to two s-wave superconducting leads. When the topological superconductor island is in the Coulomb blockade regime, we predict that a Josephson current flows between the two leads due to a nonlocal transfer of Cooper pairs mediated by the Majorana Kramers pairs. Interestingly, we find that the sign of the Josephson current is controlled by the joint parity of all four Majorana bound states on the island. Consequently, this parity-controlled Josephson effect can be used for qubit readout in Majorana-based quantum computing.
- Published
- 2018
- Full Text
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41. Topological Band Theory for Non-Hermitian Hamiltonians.
- Author
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Shen H, Zhen B, and Fu L
- Abstract
We develop the topological band theory for systems described by non-Hermitian Hamiltonians, whose energy spectra are generally complex. After generalizing the notion of gapped band structures to the non-Hermitian case, we classify "gapped" bands in one and two dimensions by explicitly finding their topological invariants. We find nontrivial generalizations of the Chern number in two dimensions, and a new classification in one dimension, whose topology is determined by the energy dispersion rather than the energy eigenstates. We then study the bulk-edge correspondence and the topological phase transition in two dimensions. Different from the Hermitian case, the transition generically involves an extended intermediate phase with complex-energy band degeneracies at isolated "exceptional points" in momentum space. We also systematically classify all types of band degeneracies.
- Published
- 2018
- Full Text
- View/download PDF
42. Chiral Topological Superconductors Enhanced by Long-Range Interactions.
- Author
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Viyuela O, Fu L, and Martin-Delgado MA
- Abstract
We study the phase diagram and edge states of a two-dimensional p-wave superconductor with long-range hopping and pairing amplitudes. New topological phases and quasiparticles different from the usual short-range model are obtained. When both hopping and pairing terms decay with the same exponent, one of the topological chiral phases with propagating Majorana edge states gets significantly enhanced by long-range couplings. On the other hand, when the long-range pairing amplitude decays more slowly than the hopping, we discover new topological phases where propagating Majorana fermions at each edge pair nonlocally and become gapped even in the thermodynamic limit. Remarkably, these nonlocal edge states are still robust, remain separated from the bulk, and are localized at both edges at the same time. The inclusion of long-range effects is potentially applicable to recent experiments with magnetic impurities and islands in 2D superconductors.
- Published
- 2018
- Full Text
- View/download PDF
43. What Controls Thermo-osmosis? Molecular Simulations Show the Critical Role of Interfacial Hydrodynamics.
- Author
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Fu L, Merabia S, and Joly L
- Abstract
Thermo-osmotic and related thermophoretic phenomena can be found in many situations from biology to colloid science, but the underlying molecular mechanisms remain largely unexplored. Using molecular dynamics simulations, we measure the thermo-osmosis coefficient by both mechanocaloric and thermo-osmotic routes, for different solid-liquid interfacial energies. The simulations reveal, in particular, the crucial role of nanoscale interfacial hydrodynamics. For nonwetting surfaces, thermo-osmotic transport is largely amplified by hydrodynamic slip at the interface. For wetting surfaces, the position of the hydrodynamic shear plane plays a key role in determining the amplitude and sign of the thermo-osmosis coefficient. Finally, we measure a giant thermo-osmotic response of the water-graphene interface, which we relate to the very low interfacial friction displayed by this system. These results open new perspectives for the design of efficient functional interfaces for, e.g., waste-heat harvesting.
- Published
- 2017
- Full Text
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44. Topological Phase Transitions in Multicomponent Superconductors.
- Author
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Wang Y and Fu L
- Abstract
We study the phase transition between a trivial and a time-reversal-invariant topological superconductor in a single-band system. By analyzing the interplay of symmetry, topology, and energetics, we show that for a generic normal state band structure, the phase transition occurs via extended intermediate phases in which even- and odd-parity pairing components coexist. For inversion-symmetric systems, the coexistence phase spontaneously breaks time-reversal symmetry. For noncentrosymmetric superconductors, the low-temperature intermediate phase is time-reversal breaking, while the high-temperature phase preserves time-reversal symmetry and has topologically protected line nodes. Furthermore, with approximate rotational invariance, the system has an emergent U(1)×U(1) symmetry, and novel topological defects, such as half vortex lines binding Majorana fermions, can exist. We analytically solve for the dispersion of the Majorana fermion and show that it exhibits small and large velocities at low and high energies. Relevance of our theory to superconducting pyrochlore oxide Cd_{2}Re_{2}O_{7} and half-Heusler materials is discussed.
- Published
- 2017
- Full Text
- View/download PDF
45. Noncollinear Magnetic Structure and Multipolar Order in Eu_{2}Ir_{2}O_{7}.
- Author
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Wang Y, Weng H, Fu L, and Dai X
- Abstract
The magnetic properties of the pyrochlore iridate material Eu_{2}Ir_{2}O_{7} (5d^{5}) have been studied based on first principles calculations, where the crystal field splitting Δ, spin-orbit coupling (SOC) λ, and Coulomb interaction U within Ir 5d orbitals all play significant roles. The ground state phase diagram has been obtained with respect to the strength of SOC and Coulomb interaction U, where a stable antiferromagnetic ground state with all-in-all-out (AIAO) spin structure has been found. In addition, another antiferromagnetic state with energy close to AIAO has also been found to be stable. The calculated nonlinear magnetization of the two stable states both have the d-wave pattern but with a π/4 phase difference, which can perfectly explain the experimentally observed nonlinear magnetization pattern. Compared with the results of the nondistorted structure, it turns out that the trigonal lattice distortion is crucial for stabilizing the AIAO state in Eu_{2}Ir_{2}O_{7}. Furthermore, besides large dipolar moments, we also find considerable octupolar moments in the magnetic states.
- Published
- 2017
- Full Text
- View/download PDF
46. Numerical Study of Quantum Hall Bilayers at Total Filling ν_{T}=1: A New Phase at Intermediate Layer Distances.
- Author
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Zhu Z, Fu L, and Sheng DN
- Abstract
We study the phase diagram of quantum Hall bilayer systems with total filing ν_{T}=1/2+1/2 of the lowest Landau level as a function of layer distances d. Based on numerical exact diagonalization calculations, we obtain three distinct phases, including an exciton superfluid phase with spontaneous interlayer coherence at small d, a composite Fermi liquid at large d, and an intermediate phase for 1.1
- Published
- 2017
- Full Text
- View/download PDF
47. Odd-Parity Superconductivity near an Inversion Breaking Quantum Critical Point in One Dimension.
- Author
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Ruhman J, Kozii V, and Fu L
- Abstract
We study how an inversion-breaking quantum critical point affects the ground state of a one-dimensional electronic liquid with repulsive interaction and spin-orbit coupling. We find that regardless of the interaction strength, the critical fluctuations always lead to a gap in the electronic spin sector. The origin of the gap is a two-particle backscattering process, which becomes relevant due to renormalization of the Luttinger parameter near the critical point. The resulting spin-gapped state is topological and can be considered as a one-dimensional version of a spin-triplet superconductor. Interestingly, in the case of a ferromagnetic critical point, the Luttinger parameter is renormalized in the opposite manner, such that the system remains nonsuperconducting.
- Published
- 2017
- Full Text
- View/download PDF
48. Interlayer Pairing Symmetry of Composite Fermions in Quantum Hall Bilayers.
- Author
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Isobe H and Fu L
- Abstract
We study the pairing symmetry of the interlayer paired state of composite fermions in quantum Hall bilayers. Based on the Halperin-Lee-Read (HLR) theory, the effect of the long-range Coulomb interaction and the internal Chern-Simons gauge fluctuation is analyzed with the random-phase approximation beyond the leading order contribution in small momentum expansion, and we observe that the interlayer paired states with a relative angular momentum l=+1 are energetically favored for filling ν=1/2+1/2 and 1/4+1/4. The degeneracy between states with ±l is lifted by the interlayer density-current interaction arising from the interplay of the long-range Coulomb interaction and the Chern-Simons term in the HLR theory.
- Published
- 2017
- Full Text
- View/download PDF
49. Topologically Entangled Rashba-Split Shockley States on the Surface of Grey Arsenic.
- Author
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Zhang P, Ma JZ, Ishida Y, Zhao LX, Xu QN, Lv BQ, Yaji K, Chen GF, Weng HM, Dai X, Fang Z, Chen XQ, Fu L, Qian T, Ding H, and Shin S
- Abstract
We discover a pair of spin-polarized surface bands on the (111) face of grey arsenic by using angle-resolved photoemission spectroscopy (ARPES). In the occupied side, the pair resembles typical nearly-free-electron Shockley states observed on noble-metal surfaces. However, pump-probe ARPES reveals that the spin-polarized pair traverses the bulk band gap and that the crossing of the pair at Γ[over ¯] is topologically unavoidable. First-principles calculations well reproduce the bands and their nontrivial topology; the calculations also support that the surface states are of Shockley type because they arise from a band inversion caused by crystal field. The results provide compelling evidence that topological Shockley states are realized on As(111).
- Published
- 2017
- Full Text
- View/download PDF
50. Suppression of Superfluid Density and the Pseudogap State in the Cuprates by Impurities.
- Author
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Erdenemunkh U, Koopman B, Fu L, Chatterjee K, Wise WD, Gu GD, Hudson EW, and Boyer MC
- Abstract
We use scanning tunneling microscopy (STM) to study magnetic Fe impurities intentionally doped into the high-temperature superconductor Bi_{2}Sr_{2}CaCu_{2}O_{8+δ}. Our spectroscopic measurements reveal that Fe impurities introduce low-lying resonances in the density of states at Ω_{1}≈4 meV and Ω_{2}≈15 meV, allowing us to determine that, despite having a large magnetic moment, potential scattering of quasiparticles by Fe impurities dominates magnetic scattering. In addition, using high-resolution spatial characterizations of the local density of states near and away from Fe impurities, we detail the spatial extent of impurity-affected regions as well as provide a local view of impurity-induced effects on the superconducting and pseudogap states. Our studies of Fe impurities, when combined with a reinterpretation of earlier STM work in the context of a two-gap scenario, allow us to present a unified view of the atomic-scale effects of elemental impurities on the pseudogap and superconducting states in hole-doped cuprates; this may help resolve a previously assumed dichotomy between the effects of magnetic and nonmagnetic impurities in these materials.
- Published
- 2016
- Full Text
- View/download PDF
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