176 citations · 596 across the 25 of their papers we have counts for
25 papers
Large scale theoretical investigation of the phase diagram of twisted bilayer MoTe at fractional fillings: agreements and contradictions with current experiments
Heqiu Li, Jiabin Yu, Xiaodong Xu +2
We present a comprehensive exact-diagonalization study of interaction-driven phases in twisted bilayer MoTe across experimentally relevant twist angles (--…
The "Moiré Capacitor Effect" and Stabilization of Fractional Chern Insulators in Rhombohedral Graphene Superlattices
Nicolas Regnault, Heqiu Li, Yves H. Kwan +2
While the necessity of a moiré potential for fractional Chern insulators (FCIs) in rhombohedral graphene-hBN superlattices, first predicted in Ref. 1, is now grounded in experiment…
Magnon-Mediated Superconductivity in a 2D Itinerant Ferromagnet with Weak Easy-plane Magnetic Anisotropy
Vladimir Calvera, Heqiu Li, Yijie Wang +2
Motivated by recent observations of superconductivity in a quarter-metal state of spin- and valley- polarized graphene multilayers, we investigate pairing within a ferromagnetic ph…
Multi-Band Exact Diagonalization and an Iteration Approach to Hunt For Fractional Chern Insulators in Rhombohedral Multilayer Graphene
Heqiu Li, B. Andrei Bernevig, Nicolas Regnault
We perform a multi-band exact diagonalization (ED) study of rhombohedral pentalayer graphene twisted on hexagonal boron nitride with a focus on fractional Chern insulators (FCI) in…
Valley polarization, magnetization, and superconductivity in bilayer graphene near the van Hove singularity
Alex Friedlan, Heqiu Li, Hae-Young Kee
The discovery of Mott insulators and superconductivity in twisted bilayer graphene has ignited intensive research into strong correlation effects in other stacking geometries. Bern…
Contrasting twisted bilayer graphene and transition metal dichalcogenides for fractional Chern insulators: an emergent gauge picture
Heqiu Li, Ying Su, Yong Baek Kim +3
The recent experimental discovery of the zero-field fractional Chern insulator (FCI) in twisted moiré superlattices has sparked immense interest in this exotic to…
Intertwined van-Hove Singularities as a Mechanism for Loop Current Order in Kagome Metals
Heqiu Li, Yong Baek Kim, Hae-Young Kee
Recent experiments on Kagome metals AVSb (A=Cs,Rb,K) indicated spontaneous time-reversal symmetry breaking in the charge density wave state in the absence of static magneti…
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…
Origin of -shifted three-dimensional charge density waves in kagome metal AVSb
Heqiu Li, Xiaoyu Liu, Yong Baek Kim +1
Understanding the nature of charge density wave (CDW) and superconductivity in kagome metal AVSb (A=Cs,Rb,K) is a recent subject of intensive study. Due to the presence of…
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…
Green's Function Approach to Interacting Higher-order Topological Insulators
Heqiu Li, Hae-Young Kee, Yong Baek Kim
The Bloch wave functions have been playing a crucial role in the diagnosis of topological phases in non-interacting systems. However, the Bloch waves are no longer applicable in th…
Finite-Frequency Topological Maxwell Modes in Mechanical Self-Dual Kagome Lattices
Hrishikesh Danawe, Heqiu Li, Kai Sun +1
In this Letter, an elastic twisted kagome lattice at a critical twist angle, called self-dual kagome lattice, is shown to exhibit peculiar finite-frequency topological modes which…
Magnetic-field Induced Topological Transitions and Thermal Conductivity in a Generalized Kitaev Model
Heqiu Li, Yong Baek Kim, Hae-Young Kee
Recent experiments on Kitaev spin liquid candidate materials reported non-monotonic behavior of thermal conductivity as a function of magnetic field, which lead to conflicting inte…
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…
Massive Dirac fermions in moiré superlattices: a route towards topological flat minibands
Ying Su, Heqiu Li, Chuanwei Zhang +2
We demonstrate a generic mechanism to realize topological flat minibands by confining massive Dirac fermions in a periodic moiré potential, which can be achieved in a heterobilayer…
Classification of phase transitions and intertwined orders in crystallographic point groups
Heqiu Li
Symmetry provides important insight in understanding the nature of phase transitions. In the presence of crystalline symmetries, new phenomena in phase transition can emerge, such…
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…
Existence of Corner Modes in Elastic Twisted Kagome Lattices
Hrishikesh Danawe, Heqiu Li, Hasan Al Ba'ba'a +1
This Letter investigates the emergence of corner modes in elastic twisted Kagome lattices at a critical twist angle, known as self-dual point. We show that a special type of corner…
Spontaneous fractional Chern insulators in transition metal dichalcogenides Moire superlattices
Heqiu Li, Umesh Kumar, Kai Sun +1
Moir{é} superlattice realized in two-dimensional heterostructures offers an exciting platform to access strongly-correlated electronic states. In this work, we study transition met…
Topological insulators and higher-order topological insulators from gauge-invariant 1D lines
Heqiu Li, Kai Sun
In this manuscript, we study the interplay between symmetry and topology with a focus on the topological index of 2D/3D topological insulators and high-order topological insu…
Pfaffian formalism for higher-order topological insulators
Heqiu Li, Kai Sun
We generalize the Pfaffian formalism, which has been playing an important role in the study of time-reversal invariant topological insulators (TIs), to 3D chiral higher-order topol…
Diagnosis of topological nodal lines with nontrivial monopole charge in the presence of rotation symmetries
Heqiu Li, Chen Fang, Kai Sun
We discuss a general diagnosis scheme for topological nodal lines protected by time-reversal symmetry and space-inversion symmetry, in the absence of spin-orbit coupling. It is sho…
Topological Protection from Random Rashba Spin-Orbit Backscattering: Ballistic Transport in a Helical Luttinger Liquid
Hong-Yi Xie, Heqiu Li, Yang-Zhi Chou +1
The combination of Rashba spin-orbit coupling and potential disorder induces a random current operator for the edge states of a 2D topological insulator. We prove that charge trans…