67 citations · 411 across the 15 of their papers we have counts for
15 papers
Magnetic Bloch States at Integer Flux Quanta Induced by Super-moiré Potential in Graphene Aligned with Twisted Boron Nitride
Yaqi Ma, Meizhen Huang, Xu Zhang +15
Two-dimensional electron systems in both magnetic fields and periodic potentials are described by Hofstadter butterfly, a fundamental problem of solid-state physics. While moiré sy…
Angle-Tuned Gross-Neveu Quantum Criticality in Twisted Bilayer Graphene: A Quantum Monte Carlo Study
Cheng Huang, Nikolaos Parthenios, Maksim Ulybyshev +4
The fascinating quantum many-body states in twisted bilayber graphene (TBG) at magic angle, due to the interplay of Coulomb interactions and the quantum metrics of flat bands, have…
Emergent Conformal Symmetry at the Multicritical Point of (2+1)D SO(5) Model with Wess-Zumino-Witten Term on Sphere
Bin-Bin Chen, Xu Zhang, Zi Yang Meng
Novel critical phenomena beyond the Landau-Ginzburg-Wilson paradigm have been long sought after. Among many candidate scenarios, the deconfined quantum critical point (DQCP) consti…
An integral algorithm of exponential observables for interacting fermions in quantum Monte Carlo simulation
Xu Zhang, Gaopei Pan, Bin-Bin Chen +2
Exponential observables, formulated as where is an extensive quantity, play a critical role in study of quantum many-body systems, examp…
Phases of (2+1)D SO(5) non-linear sigma model with a topological term on a sphere: multicritical point and disorder phase
Bin-Bin Chen, Xu Zhang, Yuxuan Wang +2
Novel critical phenomena beyond the Landau-Ginzburg-Wilson paradigm have been long sought after. Among many candidate scenarios, the deconfined quantum critical point (DQCP) consti…
Evolution from quantum anomalous Hall insulator to heavy-fermion semimetal in magic-angle twisted bilayer graphene
Cheng Huang, Xu Zhang, Gaopei Pan +4
The ground states of twisted bilayer graphene (TBG) at chiral and flat-band limit with integer fillings are known from exact solutions, while their dynamical and thermodynamical pr…
The "Sign problem" of the 3rd order anomalous Hall effect in topological magnetic materials
Xu Zhang, Kai Sun, Zi Yang Meng
The anomalous Hall effect (AHE), which provides a bridgeway between the geometry of quantum wavefunctions and transport measurements, has been a key focus of intensive studies. In…
Experimental evidence for Berry curvature multipoles in antiferromagnets
Soumya Sankar, Ruizi Liu, Xue-Jian Gao +12
Berry curvature multipoles appearing in topological quantum materials have recently attracted much attention. Their presence can manifest in novel phenomena, such as nonlinear anom…
Intrinsic nonlinear Hall effect and gate-switchable Berry curvature sliding in twisted bilayer graphene
Meizhen Huang, Zefei Wu, Xu Zhang +8
Though the observation of the quantum anomalous Hall effect and nonlocal transport response reveals nontrivial band topology governed by the Berry curvature in twisted bilayer grap…
Quantum Monte Carlo sign bounds, topological Mott insulator and thermodynamic transitions in twisted bilayer graphene model
Xu Zhang, Gaopei Pan, Bin-Bin Chen +3
We show that for magic-angle twisted bilayer graphene (TBG) away from charge neutrality, although quantum Monte Carlo (QMC) simulations suffer from the sign problem, the computatio…
Thermodynamic characteristic for correlated flat-band system with quantum anomalous Hall ground state
Gaopei Pan, Hongyu Lu, Heqiu Li +4
While the ground state phase diagram of the correlated flat-band systems have been intensively investigated, the dynamic and thermodynamic properties of such lattice models are les…
Fermion sign bounds theory in quantum Monte Carlo simulation
Xu Zhang, Gaopei Pan, Xiao Yan Xu +1
Sign problem in fermion quantum Monte Carlo (QMC) simulation appears to be an extremely hard problem. Traditional lore passing around for years tells people that when there is a si…
Superconductivity and bosonic fluid emerging from Moiré flat bands
Xu Zhang, Kai Sun, Heqiu Li +2
Although evidence of inter-valley attraction-mediated by phonon or topological fluctuations is accumulating, the origin of superconductivity in the flat-band quantum moiré material…
Dynamical properties of collective excitations in twisted bilayer Graphene
Gaopei Pan, Xu Zhang, Heqiu Li +2
Employing the recently developed momentum-space quantum Monte Carlo scheme, we study the dynamic response of single-particle and collective excitations in realistic continuum model…
Momentum space quantum Monte Carlo on twisted bilayer Graphene
Xu Zhang, Gaopei Pan, Yi Zhang +2
We report an implementation of the momentum space quantum Monte Carlo (QMC) method on the interaction model for the twisted bilayer graphene (TBG) at integer fillings. The long-ran…