Crossover of Three-Dimensional Topological Insulator of Bi2Se3 to the Two-Dimensional Limit (2009)
Zhang, Yi, He, Ke, Chang, Cui-Zu, Song, Can-Li, Wang, Lili, Chen, Xi, ...
Bi2Se3 is theoretically predicted1 and experimentally observed2,3 to be a three dimensional topological insulator. For possible applications, it is important to understand the electronic structure of...
Equivalent topological invariants of topological insulators (2009)
Wang, Zhong, Qi, Xiao-Liang, Zhang, Shou-Cheng
A time-reversal invariant topological insulator can be generally defined by the effective topological field theory with a quantized \theta coefficient, which can only take values of 0 or \pi. This...
Quasiparticle Interference on the Surface of the Topological Insulator Bi$_2$Te$_3$ (2009)
Lee, Wei-Cheng, Wu, Congjun, Arovas, Daniel P., Zhang, Shou-Cheng
The quasiparticle interference of the spectroscopic imaging scanning tunneling microscopy has been investigated for the surface states of the large gap topological insulator Bi$_2$Te$_3$ through the...
Collective modes of a helical liquid (2009)
Raghu, S., Chung, Suk Bum, Qi, Xiao-Liang, Zhang, Shou-Cheng
We study low energy collective modes and transport properties of the "helical metal" on the surface of a topological insulator. At low energies, electrical transport and spin dynamics at the surface...
Fermi Surface Topological Invariants for Time Reversal Invariant Superconductors (2009)
Qi, Xiao-Liang, Hughes, Taylor L., Zhang, Shou-Cheng
A time reversal invariant (TRI) topological superconductor has a full pairing gap in the bulk and topologically protected gapless states on the surface or at the edge. In this paper, we show that in...
Oscillatory crossover from two dimensional to three dimensional topological insulators (2009)
Liu, Chao-Xing, Zhang, HaiJun, Yan, Binghai, Qi, Xiao-Liang, Frauenheim, Thomas, Dai, Xi, ...
We investigate the crossover regime from three dimensional topological insulators $Bi_2Te_3$ and $Bi_2Se_3$ to two dimensional topological insulators with quantum spin Hall effect when the layer...
Aharonov-Bohm interference in topological insulator nanoribbons (2009)
Peng, Hailin, Lai, Keji, Kong, Desheng, Meister, Stefan, Chen, Yulin, Qi, Xiao-Liang, ...
Topological insulators represent novel phases of quantum matter with an insulating bulk gap and gapless edges or surface states. The two-dimensional topological insulator phase was predicted in HgTe...
Dynamical Axion Field in Topological Magnetic Insulators (2009)
Li, Rundong, Wang, Jing, Qi, Xiaoliang, Zhang, Shou-Cheng
Axions are very light, very weakly interacting particles postulated more than 30 years ago in the context of the Standard Model of particle physics. Their existence could explain the missing dark...
Magnetoconductance of the quantum spin Hall state (2009)
Maciejko, Joseph, Qi, Xiao-Liang, Zhang, Shou-Cheng
We study the edge magnetoconductance of a quantum spin Hall insulator in the presence of quenched nonmagnetic disorder. For a finite magnetic field B and disorder strength W on the order of the bulk...
Detecting the Majorana fermion surface state of $^3$He-B through spin relaxation (2009)
Chung, Suk Bum, Zhang, Shou-Cheng
The concept of the Majorana fermion has been postulated more than eighty years ago; however, this elusive particle has never been observed in nature. The non-local character of the Majorana fermion...
Nonlocal edge state transport in the quantum spin Hall state (2009)
Roth, Andreas, Bruene, Christoph, Buhmann, Hartmut, Molenkamp, Laurens W., Maciejko, Joseph, Qi, Xiao-Liang, ...
We present direct experimental evidence for nonlocal transport in HgTe quantum wells in the quantum spin Hall regime, in the absence of any external magnetic field. The data conclusively show that...
Emergence of the persistent spin helix in semiconductor quantum wells (2009)
Koralek, Jake D., Weber, Chris, Orenstein, Joe, Bernevig, Andrei, Zhang, Shou-Cheng, Mack, Shawn, ...
According to Noethers theorem, for every symmetry in nature there is a corresponding conservation law. For example, invariance with respect to spatial translation corresponds to conservation of...
Electronic Structures and Surface States of Topological Insulator Bi$_{1-x}$Sb$_{x}$ (2009)
Zhang, Hai-Jun, Liu, Chao-Xing, Qi, Xiao-Liang, Deng, Xiao-Yu, Dai, Xi, Zhang, Shou-Cheng, ...
We investigate the electronic structures of the alloyed Bi$_{1-x}$Sb$_x$ compounds based on first-principle calculations including spin-orbit coupling (SOC), and calculate the surface states of...
Kondo effect in the helical edge liquid of the quantum spin Hall state (2009)
Maciejko, Joseph, Liu, Chaoxing, Oreg, Yuval, Qi, Xiao-Liang, Wu, Congjun, Zhang, Shou-Cheng
Following the recent observation of the quantum spin Hall (QSH) effect in HgTe quantum wells, an important issue is to understand the effect of impurities on transport in the QSH regime. Using linear...
Supersymmetric Valence Bond Solid States (2009)
Arovas, Daniel P., Hasebe, Kazuki, Qi, Xiao-Liang, Zhang, Shou-Cheng
In this work we investigate the supersymmetric version of the valence bond solid (SVBS) state. In one dimension, the SVBS states continuously interpolate between the valence bond states for integer...
Topological Insulators at Room Temperature (2008)
Zhang, Haijun, Liu, Chao-Xing, Qi, Xiao-Liang, Dai, Xi, Fang, Zhong, Zhang, Shou-Cheng
Topological insulators are new states of quantum matter with surface states protected by the time-reversal symmetry. In this work, we perform first-principle electronic structure calculations for...
Seeing the magnetic monopole through the mirror of topological surface states (2008)
Qi, Xiao-Liang, Li, Rundong, Zang, Jiadong, Zhang, Shou-Cheng
Existence of the magnetic monopole is compatible with the fundamental laws of nature, however, this illusive particle has yet to be detected experimentally. In this work, we show that an electric...
Algebraic spin liquid in an exactly solvable spin model (2008)
Yao, Hong, Zhang, Shou-Cheng, Kivelson, Steven A.
We have proposed an exactly solvable quantum spin-3/2 model on a square lattice. Its ground state is a quantum spin liquid with a half integer spin per unit cell. The fermionic excitations are...
Field-induced Gap and Quantized Charge Pumping in Nano-helix (2008)
Qi, Xiao-Liang, Zhang, Shou-Cheng
We propose several novel physical phenomena based on nano-scale helical wires. Applying a static electric field transverse to the helical wire induces a metal to insulator transition, with the band...
Time-reversal symmetry breaking pairing state in FeAs based superconductors (2008)
Lee, Wei-Cheng, Zhang, Shou-Cheng, Wu, Congjun
We investigate the competition between the extended $s_{\pm}$-wave and $d_{x^2-y^2}$-wave pairing order parameters in the iron-based superconductors. Because of the frustrating pairing interactions...
Topological states in a transition metal oxide Na2IrO3 (2008)
Shitade, Atsuo, Katsura, Hosho, Qi, Xiao-Liang, Zhang, Shou-Cheng, Nagaosa, Naoto
The electronic state of an Ir oxide, Na$_2$IrO$_3$ with the honeycomb structure is analyzed theoretically as a representative system where both the spin-orbit interaction and the electron correlation...
Magnetic impurities on the surface of a topological insulator (2008)
Liu, Qin, Liu, Chao-Xing, Xu, Cenke, Qi, Xiao-Liang, Zhang, Shou-Cheng
The surface states of a topological insulator are described by an emergent relativistic massless Dirac equation in 2+1 dimensions. In contrast to graphene, there is an odd number of Dirac points, and...
Pairing strengths for a two orbital model of the Fe-pnictides (2008)
Qi, Xiao-Liang, Raghu, S., Liu, Chao-Xing, Scalapino, D. J., Zhang, Shou-Cheng
Using an RPA approximation, we have calculated the strengths of the singlet and triplet pairing interactions which arise from the exchange of spin and orbital fluctuations for a 2-orbital model of...
A minimal two-band model for the superconducting Fe-pnictides (2008)
Raghu, S., Qi, Xiao-Liang, Liu, Chao-Xing, Scalapino, D., Zhang, Shou-Cheng
Following the discovery of the Fe-pnictide superconductors, LDA band structure calculations showed that the dominant contributions to the spectral weight near the Fermi energy came from the Fe 3d...
Topological Superconductivity and Superfluidity (2008)
Qi, Xiao-Liang, Hughes, Taylor L., Raghu, Srinivas, Zhang, Shou-Cheng
We construct time reversal invariant topological superconductors and superfluids in two and three dimensions which are analogous to the recently discovered quantum spin Hall and three-d $Z_2$...
Topological Field Theory of Time-Reversal Invariant Insulators (2008)
Qi, Xiao-Liang, Hughes, Taylor, Zhang, Shou-Cheng
We show that the fundamental time reversal invariant (TRI) insulator exists in 4+1 dimensions, where the effective field theory is described by the 4+1 dimensional Chern-Simons theory and the...
Quantum Anomalous Hall Effect in Hg$_{1-y}$Mn$_{y}$Te Quantum Wells (2008)
Liu, Chao-Xing, Qi, Xiao-Liang, Dai, Xi, Fang, Zhong, Zhang, Shou-Cheng
The quantum Hall effect is usually observed when the two-dimensional electron gas is subjected to an external magnetic field, so that their quantum states form Landau levels. In this work we predict...
Quantum Spin Hall Effect in Inverted Type II Semiconductors (2008)
Liu, Chaoxing, Hughes, Taylor L., Qi, Xiao-Liang, Wang, Kang, Zhang, Shou-Cheng
The quantum spin Hall (QSH) state is a topologically non-trivial state of quantum matter which preserves time-reversal symmetry; it has an energy gap in the bulk, but topologically robust gapless...
The Quantum Spin Hall Effect: Theory and Experiment (2008)
Koenig, Markus, Buhmann, Hartmut, Molenkamp, Laurens W., Hughes, Taylor L., Liu, Chao-Xing, Qi, Xiao-Liang, ...
The search for topologically non-trivial states of matter has become an important goal for condensed matter physics. Recently, a new class of topological insulators has been proposed. These...
Spin Charge Separation in the Quantum Spin Hall State (2007)
Qi, Xiao-Liang, Zhang, Shou-Cheng
The quantum spin Hall state is a topologically non-trivial insulator state protected by the time reversal symmetry. We show that such a state always leads to spin-charge separation in the presence of...
Fractional Charge and Quantized Current in the Quantum Spin Hall State (2007)
Qi, Xiao-Liang, Hughes, Taylor L., Zhang, Shou-Cheng
A profound manifestation of topologically non-trivial states of matter is the occurrence of fractionally charged elementary excitations. The quantum spin Hall insulator state is a fundamentally novel...
Quantum Spin Hall Insulator State in HgTe Quantum Wells (2007)
Koenig, Markus, Wiedmann, Steffen, Bruene, Christoph, Roth, Andreas, Buhmann, Hartmut, Molenkamp, Laurens W., ...
Recent theory predicted that the Quantum Spin Hall Effect, a fundamentally novel quantum state of matter that exists at zero external magnetic field, may be realized in HgTe/(Hg,Cd)Te quantum wells....
Topological Mott Insulators (2007)
Raghu, S., Qi, Xiao-Liang, Honerkamp, C., Zhang, Shou-Cheng
We consider extended Hubbard models with repulsive interactions on a Honeycomb lattice and the transitions from the semi-metal phase at half-filling to Mott insulating phases. In particular, due to...
Helical edge and surface states in HgTe quantum wells and bulk insulators (2007)
Dai, Xi, Hughes, Taylor L., Qi, Xiao-Liang, Fang, Zhong, Zhang, Shou-Cheng
The quantum spin Hall (QSH) effect is the property of a new state of matter which preserves time-reversal, has an energy gap in the bulk, but has topologically robust gapless states at the edge....
Spin accumulation from the non-Abelian Aharonov-Bohm effect (2007)
Liu, Qin, Ma, Tianxing, Zhang, Shou-Cheng
Recently, it has been shown that the spin-orbit coupling (SOC) of the Dresselhaus type in $[110]$ quantum wells can be mathematically removed by a non-Abelian gauge transformation. In the presence of...
Current carrying ground state in a bilayer model of strongly correlated systems (2007)
Capponi, Sylvain, Wu, Congjun, Zhang, Shou-Cheng
Strongly interacting systems have been conjectured to spontaneously develop current carrying ground states under certain conditions. We demonstrate the existence of a commensurate staggered...
Non-diffusive spin dynamics in a two-dimensional electron gas (2006)
Weber, Christopher P., Orenstein, Joseph, Bernevig, B. Andrei, Zhang, Shou-Cheng, Stephens, Jason, Awschalom, David D.
We describe measurements of spin dynamics in the two-dimensional electron gas in GaAs/GaAlAs quantum wells. Optical techniques, including transient spin-grating spectroscopy, are used to probe the...
Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells (2006)
Bernevig, B. Andrei, Hughes, Taylor L., Zhang, Shou-Cheng
We show that the Quantum Spin Hall Effect, a state of matter with topological properties distinct from conventional insulators, can be realized in HgTe/CdTe semiconductor quantum wells. By varying...
Fermi liquid instabilities in the spin channel (2006)
Wu, Congjun, Sun, Kai, Fradkin, Eduardo, Zhang, Shou-Cheng
We study the Fermi surface instabilities of the Pomeranchuk type in the spin triplet channel with high orbital partial waves ($F_{l}^a ~(l>0)$). The ordered phases are classified into two classes,...
Non-diffusive spin dynamics in a two-dimensional electron gas (2006)
Weber, C. P., Orenstein, J., Bernevig, B. Andrei, Zhang, Shou-Cheng, Stephens, Jason, Awschalom, D. D.
We describe measurements of spin dynamics in the two-dimensional electron gas in GaAs/GaAlAs quantum wells. Optical techniques, including transient spin-grating spectroscopy, are used to probe the...
Band Collapse and the Quantum Hall Effect in Graphene (2006)
Bernevig, B. Andrei, Hughes, Taylor L., Chen, Han-Dong, Wu, Congjun, Zhang, Shou-Cheng
The recent Quantum Hall experiments in graphene have confirmed the theoretically well-understood picture of the quantum Hall (QH) conductance in fermion systems with continuum Dirac spectrum. In this...
Spin-orbit gap of graphene: First-principles calculations (2006)
Yao, Yugui, Ye, Fei, Qi, Xiao-Liang, Zhang, Shou-Cheng, Fang, Zhong
Even though graphene is a low energy system consisting of the two dimensional honeycomb lattice of carbon atoms, its quasi-particle excitations are fully described by the 2+1 dimensional relativistic...
An Exact SU(2) Symmetry and Persistent Spin Helix in a Spin-Orbit Coupled System (2006)
Bernevig, B. Andrei, Orenstein, J., Zhang, Shou-Cheng
Spin-orbit coupled systems generally break the spin rotation symmetry. However, for a model with equal Rashba and Dresselhauss coupling constant (the ReD model), and for the $[110]$ Dresselhauss...
Qi, Xiao-Liang, Wu, Yong-Shi, Zhang, Shou-Cheng
We prove a general theorem on the relation between the bulk topological quantum number and the edge states in two dimensional insulators. It is shown that whenever there is a topological order in...
Quintet pairing and non-Abelian vortex string in spin-3/2 cold atomic systems (2005)
Wu, Congjun, Hu, Jiangping, Zhang, Shou-Cheng
We study the s-wave quintet Cooper pairing phase ($S_{tot}=2$) in spin-3/2 cold atomic systems and identify various novel features which do not appear in the spin-1/2 counterpart. A single quantum...
The Helical Liquid and the Edge of Quantum Spin Hall Systems (2005)
Wu, Congjun, Bernevig, B. Andrei, Zhang, Shou-Cheng
The edge states of the recently proposed quantum spin Hall systems constitute a new symmetry class of one-dimensional liquids dubbed the ``helical liquid'', where the spin orientation is determined...
Exact spontaneous plaquette ground states for high-spin ladder models (2005)
Chen, Shu, Wu, Congjun, Zhang, Shou-Cheng, Wang, Yupeng
We study the exchange physics in high spin Mott insulating systems with $S=3/2$ which is realizable in ultracold atomic systems. The high symmetry of SO(5) or SU(4) therein renders stronger quantum...
Wu, Congjun, Zaanen, Jan, Zhang, Shou-Cheng
We study the effects of spin-orbit coupling in the $d$-density wave (DDW) phase. In the low-temperature orthorhombic phase of La$_{2-x}$Ba$_x$CuO$_4$, we find that spin-orbit coupling induces a...
Qi, Xiao-Liang, Wu, Yong-Shi, Zhang, Shou-Cheng
We propose models of two dimensional paramagnetic semiconductors where the intrinsic spin Hall effect is exactly quantized in integer units of a topological charge. The model describes a topological...
Quantum Spin Hall Effect (2005)
Bernevig, B. Andrei, Zhang, Shou-Cheng
The quantum Hall liquid is a novel state of matter with profound emergent properties such as fractional charge and statistics. Existence of the quantum Hall effect requires breaking of the time...
Orbitronics: the Intrinsic Orbital Hall Effect in p-Doped Silicon (2005)
Bernevig, B. Andrei, Hughes, Taylor L., Zhang, Shou-Cheng
The spin Hall effect depends crucially on the intrinsic spin-orbit coupling of the energy band. Because of the smaller spin-orbit coupling in silicon, the spin Hall effect is expected to be much...
Intrinsic Spin-Hall Effect in n-Doped Bulk GaAs (2004)
Bernevig, B. Andrei, Zhang, Shou-Cheng
We show that the bulk Dresselhauss ($k^3$) spin-orbit coupling term leads to an intrinsic spin-Hall effect in n-doped bulk GaAs, but without the appearance of uniform magnetization. The spin-Hall...
Intrinsic Spin Hall Effect in the Two Dimensional Hole Gas (2004)
Bernevig, B. Andrei, Zhang, Shou-Cheng
We show that two types of spin-orbit coupling in the 2 dimensional hole gas (2DHG), with and without inversion symmetry breaking, contribute to the intrinsic spin Hall...
Maxwell Equation for the Coupled Spin-Charge Wave Propagation (2004)
Bernevig, B. Andrei, Yu, Xiaowei, Zhang, Shou-Cheng
We show that the dissipationless spin current in the ground state of the Rashba model gives rise to a reactive coupling between the spin and charge propagation, which is formally identical to the...
Global Phase Diagram of the High Tc Cuprates (2004)
Chen, Han-Dong, Capponi, Sylvain, Alet, Fabien, Zhang, Shou-Cheng
The high-Tc cuprates have a complex phase diagram with many competing phases. We propose a bosonic effective quantum Hamiltonian based on the projected SO(5) model with extended interactions, which...
Antiferromagnetism and Hole Pair Checkerboard in the Vortex State of High Tc Superconductors (2004)
Chen, Han-Dong, Hu, Jian-Ping, Capponi, Sylvain, Arrigoni, Enrico, Zhang, Shou-Cheng
We propose a microscopic state for the vortex phase of BSCO superconductors. Around the vortex core or above Hc2, the d wave hole pairs form a checkerboard localized in the antiferromagnetic...
Semiclassical Time Evolution of the Holes from Luttinger Hamiltonian (2004)
Jiang, Z. F., Li, R. D., Zhang, Shou-Cheng, Liu, W. M.
We study the semi-classical motion of holes by exact numerical solution of the Luttinger model. The trajectories obtained for the heavy and light holes agree well with the higher order corrections to...
Magic Doping Fractions in High-Temperature Superconductors (2004)
Komiya, Seiki, Chen, Han-Dong, Zhang, Shou-Cheng, Ando, Yoichi
We report hole-doping dependence of the in-plane resistivity \rho_{ab} in a cuprate superconductor La_{2-x}Sr_{x}CuO_{4}, carefully examined using a series of high-quality single crystals. Our...
Spin Splitting and Spin Current in Strained Bulk Semiconductors (2004)
Bernevig, B. Andrei, Zhang, Shou-Cheng
We present a theory for two recent experiments in bulk strained semiconductors \cite{kato1, kato2} and show that a new, previously overlooked, strain spin-orbit coupling term may play a fundamental...
Wu, Congjun, Zhang, Shou-Cheng
Quantum Monte-Carlo (QMC) simulations involving fermions have the notorious sign problem. Some well-known exceptions of the auxiliary field QMC algorithm rely on the factorizibility of the fermion...
Murakami, Shuichi, Nagaosa, Naoto, Zhang, Shou-Cheng
Recent theories predict dissipationless spin current induced by an electric field in doped semiconductors. Nevertheless, the charge current is still dissipative in these systems. In this work, we...
SO(5) Theory of Antiferromagnetism and Superconductivity (2004)
Demler, Eugene, Hanke, Werner, Zhang, Shou-Cheng
Antiferromagnetism and superconductivity are both fundamental and common states of matter. In many strongly correlated systems, including the high Tc cuprates, the heavy fermion compounds and the...
Current Carrying Ground State in a Bi-layer Model (2004)
Capponi, Sylvain, Wu, Congjun, Zhang, Shou-Cheng
Strongly interacting systems have been conjectured to spontaneously develop current carrying ground states under certain conditions. We conclusively demonstrate the existence of a commensurate...
Pair Density Wave in the Pseudogap State of High Temperature Superconductors (2004)
Chen, Han-Dong, Vafek, Oskar, Yazdani, Ali, Zhang, Shou-Cheng
Recent scanning tunneling microscopy (STM) experiments of Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ have shown evidence of real-space organization of electronic states at low energies in the pseudogap...
Global Phase Diagram of the High Tc Cuprates (2003)
Chen, Han-Dong, Capponi, Sylvain, Alet, Fabien, Zhang, Shou-Cheng
The high Tc cuprates have a complex phase diagram with many competing phases. We propose a bosonic effective quantum Hamiltonian based on the projected SO(5) model with extended interactions, which...
Dynamic generation of spin orbit coupling (2003)
Wu, Congjun, Zhang, Shou-Cheng
Spin-orbit coupling plays an important role in determining the properties of solids, and is crucial for spintronics device applications. Conventional spin-orbit coupling arises microscopically from...
Global Phase Diagram of the High Tc Cuprates (2003)
Chen, Han-Dong, Capponi, Sylvain, Alet, Fabien, Zhang, Shou-Cheng
The high-Tc cuprates have a complex phase diagram with many competing phases. We propose a bosonic effective quantum Hamiltonian based on the projected SO(5) model with extended interactions, which...
Global Phase Diagram of the High Tc Cuprates (2003)
Chen, Han-Dong, Capponi, Sylvain, Alet, Fabien, Zhang, Shou-Cheng
The high-Tc cuprates have a complex phase diagram with many competing phases. We propose a bosonic effective quantum Hamiltonian based on the projected SO(5) model with extended interactions, which...
Dissipationless Spin Current in Anisotropic p-Doped Semiconductors (2003)
Bernevig, Bogdan A., Hu, JiangPing, Mukamel, Eran, Zhang, Shou-Cheng
Recently, dissipationless spin current has been predicted for the p-doped semiconductors with spin-orbit coupling. Here we investigate the effect of spherical symmetry breaking on the dissipationless...
Quantitative Test of SO(5) Symmetry in the Vortex State of $Nd_{1.85}Ce_{0.15}CuO_4$ (2003)
Chen, Han-Dong, Wu, Congjun, Zhang, Shou-Cheng
By numerically solving models with competing superconducting and antiferromagnetic orders, we study the magnetic field dependence of the antiferromagnetic moment in both the weak and strong field...
Non-abelian Berry's phase and Chern numbers in higher spin pairing condensates (2003)
Chern, Chyh-Hong, Chen, Han-Dong, Wu, Congjun, Hu, Jiang-Ping, Zhang, Shou-Cheng
We show that the non-Abelian Berry phase emerges naturally in the s-wave and spin quintet pairing channel of spin-3/2 fermions. The topological structure of this pairing condensate is characterized...
SU(2) Non-Abelian Holonomy and Dissipationless Spin Current in Semiconductors (2003)
Murakami, Shuichi, Nagaosa, Naoto, Zhang, Shou-Cheng
Following our previous work [S. Murakami, N. Nagaosa, S. C. Zhang, Science 301, 1348 (2003)] on the dissipationless quantum spin current, we present an exact quantum mechanical calculation of this...
Reply to the comment cond-mat/0308067 (2003)
Kang, H. J., Dai, Pengcheng, Lynn, J. W., Matsuura, M., Thompson, J. R., Zhang, Shou-Cheng, ...
Mang et al. report the observation of a cubic (Nd,Ce)2O3 impurity phase grown epitaxially in annealed samples of electron-doped Nd2-xCexCuO4 (NCCO) and argue that our observed magnetic scattering in...
Dissipationless Quantum Spin Current at Room Temperature (2003)
Murakami, Shuichi, Nagaosa, Naoto, Zhang, Shou-Cheng
While microscopic laws of physics are invariant under the reversal of the arrow of time, the transport of energy and information in most devices is an irreversible process. It is this irreversibility...
Exact SO(5) Symmetry in spin 3/2 fermionic system (2003)
Wu, Congjun, Hu, Jiang-ping, Zhang, Shou-cheng
The spin 3/2 fermion models with contact interactions have a {\it generic} SO(5) symmetry without any fine-tuning of parameters. Its physical consequences are discussed in both the continuum and...
Vortex configurations of bosons in an optical lattice (2002)
Wu, Congjun, Chen, Han-dong, Hu, Jiang-ping, Zhang, Shou-Cheng
The single vortex problem in a strongly correlated bosonic system is investigated self-consistently within the mean-field theory of the Bose-Hubbard model. Near the superfluid-Mott transition, the...
Exact microscopic wave function for a topological quantum membrane (2002)
The higher dimensional quantum Hall liquid constructed recently supports stable topological membrane excitations. Here we introduce a microscopic interacting Hamiltonian and present its exact ground...
To see a world in a grain of sand (2002)
Throughout John Wheeler's career, he wrestled with big issues like the fundamental length, the black hole and the unification of quantum mechanics and relativity. In this essay, I argue that solid...
Scaling properties of the projected SO(5) model in three dimensions (2002)
Jöstingmeier, M., Dorneich, A., Arrigoni, E., Hanke, W., Zhang, Shou-Cheng
We study the scaling properties of the quantum ``projected'' SO(5) model in three dimensions by means of a highly accurate Quantum-Monte-Carlo analysis. Within the parameter regime studied...
Effective field theory description of the higher dimensional quantum Hall liquid (2002)
Bernevig, B. Andrei, Chern, Chyh-Hong, Hu, Jiang-Ping, Toumbas, Nicolaos, Zhang, Shou-Cheng
We derive an effective topological field theory model of the four dimensional quantum Hall liquid state recently constructed by Zhang and Hu. Using a generalization of the flux attachment...
Antiferromagnetism and hole pair checkerboard in the vortex state of high Tc superconductors (2002)
Chen, Han-Dong, Hu, Jiang-Ping, Capponi, Sylvain, Arrigoni, Enrico, Zhang, Shou-Cheng
We propose a microscopic state for the vortex phase of BSCO superconductors. Around the vortex core or above H_{c2}, the d wave hole pairs form a checkerboard localized in the commensurate...
Antiferromagnetism and Hole Pair Checkerboard in the Vortex State of High Tc Superconductors (2002)
Chen, Han-Dong, Hu, Jian-Ping, Capponi, Sylvain, Arrigoni, Enrico, Zhang, Shou-Cheng
We propose a microscopic state for the vortex phase of BSCO superconductors. Around the vortex core or above Hc2, the d wave hole pairs form a checkerboard localized in the antiferromagnetic...
Antiferromagnetism and Hole Pair Checkerboard in the Vortex State of High Tc Superconductors (2002)
Chen, Han-Dong, Hu, Jian-Ping, Capponi, Sylvain, Arrigoni, Enrico, Zhang, Shou-Cheng
We propose a microscopic state for the vortex phase of BSCO superconductors. Around the vortex core or above Hc2, the d wave hole pairs form a checkerboard localized in the antiferromagnetic...
Tuning order in cuprate superconductors (2002)
Sachdev, Subir, Zhang, Shou-Cheng
This article presents our perspective on STM measurements by Hoffman et al. (cond-mat/0201348) of the vortex lattice in BSCCO. We discuss implications of these measurements for various theories of...
Collective excitations at the boundary of a 4D quantum Hall droplet (2001)
Hu, Jiangping, Zhang, Shou-Cheng
In this work we investigate collective excitations at the boundary of a recently constructed 4D quantum Hall state. Local bosonic operators for creating these collective excitations can be...
A Four Dimensional Generalization of the Quantum Hall Effect (2001)
Zhang, Shou-Cheng, Hu, Jiangping
We construct a generalization of the quantum Hall effect, where particles move in four dimensional space under a SU(2) gauge field. This system has a macroscopic number of degenerate single particle...
Theory of Static and Dynamic Antiferromagnetic Vortices in LSCO Superconductors (2001)
Hu, Jiang-Ping, Zhang, Shou-Cheng
A key prediction of the SO(5) theory is the antiferromagnetic vortex state. Recent neutron scattering experiment on LSCO superconductors revealed enhanced antiferromagnetic order in the vortex state....
Dispersoin of the \pi resonance (2001)
Hu, Jiangping, Zhang, Shou-Cheng
We study the dispersion of the $\pi$ resonance in the superconducting state within the projected SO(5) model\cite{project}. Away from the the commensurate momentum, the propagation of the $\pi$...
Current Induced Magnetization Switching in Small Domains of Different Anisotropies (2000)
Bazaliy, Ya. B., Jones, B. A., Zhang, Shou-Cheng
Several recent experimental studies have confirmed the possibility of switching the magnetization direction in the small magnetic domains by pumping large spin-polarized currents through them. On the...
How to experimentally measure the number 5 of the SO(5) theory? (2000)
Hu, Jiang-Ping, Zhang, Shou-Cheng
According to Wilson's theory of critical phenomena, critical exponents are universal functions of $d$, the dimension of space, and $n$, the dimension of the symmetry group. SO(5) theory of...
SO(5) Superconductors in a Zeeman Magnetic Field (1999)
Hu, Jiang-Ping, Zhang, Shou-Cheng
The generic symmetry of a system under a uniform Zeeman magnetic field is U(1) x U(1). However, we show that SO(5) models in the presence of a finite chemical potential and a finite Zeeman magnetic...
Zacher, Marc G., Hanke, Werner, Arrigoni, Enrico, Zhang, Shou-Cheng
Recent angle resolved photoemission data, which found evidence for a d-wave-like modulation of the antiferromagnetic gap, suggest an intimate interrelation between the antiferromagnetic insulator and...
Hanke, Werner, Zacher, Marc G., Arrigoni, Enrico, Zhang, Shou-Cheng
Recent angle resolved photoemission (ARPES) data, which found evidence for a d-wave-like modulation of the antiferromagnetic gap, suggest an intimate interrelation between the antiferromagnetic...
Zhang, Shou-Cheng, Hu, Jiang-Ping, Arrigoni, Enrico, Hanke, Werner, Auerbach, Assa
We construct a class of projected SO(5) models where the Gutzwiller constraint of no-double-occupancy is implemented exactly. We introduce the concept of projected SO(5) symmetry where all static...
Demler, Eugene, Zhang, Shou-Cheng
We review the explanation for resonant neutron scattering experiments in $YBa_2Cu_3O_{6+\delta}$ and $Bi_2 Sr_2 Ca_2 O_{8+\delta}$ materials from the point of view of triplet excitation in the...
Werner Hanke, Marc Zacher, Enrico Arrigoni, Shou-Cheng Zhang
Recent photoemission data, which found evidence for a d-wave-like modulation of the antiferromagnetic (AF) gap, suggest an intimate interrelation between the AF insulator and the superconductor (SC)...
A Progress Report on the SO(5) Theory of High T_c Superconductivity (1998)
In this talk I give a brief update on the recent progress in the SO(5) theory of high T_c superconductivity (Science, 275: 1089,1997). Reviewed topics include SO(5) ladders, the unification of BCS...
Quantitative Determination of a Microscopic Mechanism of High Tc Superconductivity (1998)
Demler, Eugene, Zhang, Shou-Cheng
Within the t-J model of copper-oxides, the condensation energy can be related to the change in the dynamical spin structure factor between the superconducting and the normal states. By analyzing...
Non-Abelian Holonomy of BCS and SDW Quasi-particles (1998)
Demler, Eugene, Zhang, Shou-Cheng
In this work we investigate properties of fermions in the SO(5) theory of high Tc superconductivity. We show that the adiabatic time evolution of a SO(5) superspin vector leads to a non-Abelian SU(2)...
Dynamics of an SO(5) symmetric ladder model (1998)
Eder, R., Dorneich, A., Zacher, M. G., Hanke, W., Zhang, Shou-Cheng
We discuss properties of an exactly SO(5) symmetric ladder model. In the strong coupling limit we demonstrate how the SO(3)-symmetric description of spin ladders in terms of bond Bosons can be...
An SO(5) Symmetric Ladder (1997)
Scalapino, D., Zhang, Shou-Cheng, Hanke, W.
We construct an SO(5) symmetric electron model on a two-chain ladder with purely local interactions on a rung. The ground state phase diagram of this model is determined in the strong-coupling limit....
Pi excitation of the t-J model (1997)
Demler, Eugene, Kohno, Hiroshi, Zhang, Shou-Cheng
In this paper, we present analytical and numerical calculations of the pi resonance in the t-J model. We show in detail how the pi resonance in the particle-particle channel couples to and appears in...
Recent Developments in the SO(5) Theory of High $T_c$ Superconductivity (1997)
In this talk I outline the general strategy behind the SO(5) theory of high $T_c$ superconductivity. Progress in the direction of exact SO(5) models, numerical exact diagonalization and possible...
Microscopic Electron Models with Exact SO(5) Symmetry (1997)
Rabello, Silvio, Kohno, Hiroshi, Demler, Eugene, Zhang, Shou-Cheng
We construct a class of microscopic electron models with exact SO(5) symmetry between antiferromagnetic and d-wave superconducting ground states. There is an exact one-to-one correspondence between...
Bazaliy, Ya. B., Jones, B. A., Zhang, Shou-Cheng
We derive a continuum equation for the magnetization of a conducting ferromagnet in the presence of a spin-polarized current. Current effects enter in the form of a topological term in the...
Response to Greiter's Comment (1997)
Demler, Eugene, Zhang, Shou-Cheng, Meixner, Stefan, Hanke, Werner
Greiter claimed erroneously that the pi-excitation of the Hubbard model has an energy of the order of U. This mistake originates from a inconsistent treatment of the two particle Hartree energy and...
The SO(5) theory of high T_c superconductivity (1997)
This paper gives a simple introduction to the SO(5) theory of high T_c superconductivity. Current status and relation to experiments are summarized.
Superconducting Vortex with Antiferromagnetic Core (1997)
Arovas, Daniel P., Berlinsky, A. J., Kallin, C., Zhang, Shou-Cheng
We show that a superconducting vortex in underdoped high T_c superconductors could have an antiferromagnetic core. This type of vortex configuration arises as a topological solution in the recently...
Finite-Size Studies on the SO(5) Symmetry of the Hubbard Model (1997)
Meixner, Stefan, Hanke, Werner, Demler, Eugene, Zhang, Shou-Cheng
We present numerical evidence for the approximate SO(5) symmetry of the Hubbard model on a 10 site cluster. Various dynamic correlation functions involving the $\pi$ operators, the generators of the...
SO(5) Quantum Nonlinear sigma Model Theory of the High Tc Superconductivity (1996)
We show that the complex phase diagram of high $T_c$ superconductors can be deduced from a simple symmetry principle, a $SO(5)$ symmetry which unifies antiferromagnetism with $d$ wave...
Demler, Eugene, Zhang, Shou-Cheng, Bulut, Nejat, Scalapino, Douglas J.
In this series of papers we present a detailed study of the particle--particle collective excitations of the Hubbard model, and their contribution to the density and spin excitation spectrum. In the...
Duality and Universality for the Chern-Simons bosons (1995)
Pryadko, Leonid P., Zhang, Shou-Cheng
By mapping the relativistic version of the Chern-Simons-Landau-Ginzburg theory in 2+1 dimensions to the 3D lattice Villain x-y model coupled with the Chern-Simons gauge field, we investigate phase...
Theory of the Resonant Neutron Scattering of High $T_c$ Superconductors (1995)
Demler, Eugene, Zhang, Shou-Cheng
Recent polarized neutron scattering experiments on $YBa_2 Cu_3 O_7$ have revealed a sharp spectral peak at the $(\pi,\pi)$ in reciprocal lattice centered around the energy transfer of $41\ meV$. We...
Moon, K., Mori, H., Yang, Kun, Girvin, S. M., MacDonald, A. H., Zheng, L., ...
At strong magnetic fields double-layer two-dimensional-electron-gas systems can form an unusual broken symmetry state with spontaneous inter-layer phase coherence. In this paper we explore the rich...
Fluctuation-Induced First Order Transition between the Quantum Hall Liquid and Insulator (1994)
Pryadko, Leonid, Zhang, Shou-Cheng
We study the phase transition between the quantum Hall liquid state and the insulating state within the framework of the Chern-Simons-Landau-Ginzburg theory of the quantum Hall effect. For the...
Collective excitations in double-layer quantum Hall systems (1994)
MacDonald, A. H., Zhang, Shou-Cheng
We study the collective excitation spectra of double-layer quantum-Hall systems using the single mode approximation. The double-layer in-phase density excitations are similar to those of a...
Quantum Ferromagnetism and Phase Transitions in Double-Layer Quantum Hall Systems (1993)
Yang, Kun, Moon, K., Zheng, L., MacDonald, A. H., Girvin, S. M., Yoshioka, D., ...
Double layer quantum Hall systems have interesting properties associated with interlayer correlations. At $\nu =1/m$ where $m$ is an odd integer they exhibit spontaneous symmetry breaking equivalent...