275 citations · 945 across the 8 of their papers we have counts for
8 papers
Phase diagram of twisted bilayer graphene at filling factor
Fang Xie, Jian Kang, B. Andrei Bernevig +2
We study the correlated insulating phases of twisted bilayer graphene (TBG) in the absence of lattice strain at integer filling . Using the self-consistent Hartree-Fock met…
TSTG II: Projected Hartree-Fock Study of Twisted Symmetric Trilayer Graphene
Fang Xie, Nicolas Regnault, Dumitru Călugăru +2
The Hamiltonian of the magic-angle twisted symmetric trilayer graphene (TSTG) can be decomposed into a TBG-like flat band Hamiltonian and a high-velocity Dirac fermion Hamiltonian.…
TSTG I: Single-Particle and Many-Body Hamiltonians and Hidden Non-local Symmetries of Trilayer Moiré Systems with and without Displacement Field
Dumitru Călugăru, Fang Xie, Zhi-Da Song +3
We derive the Hamiltonian for trilayer moiré systems with the Coulomb interaction projected onto the bands near the charge neutrality point. Motivated by the latest experimental re…
Evidence for a Monolayer Excitonic Insulator
Yanyu Jia, Pengjie Wang, Cheng-Li Chiu +19
The interplay between topology and correlations can generate a variety of quantum phases, many of which remain to be explored. Recent advances have identified monolayer WTe2 as a p…
Twisted bilayer graphene.VI. An Exact Diagonalization Study of Twisted Bilayer Graphene at Non-Zero Integer Fillings
Fang Xie, Aditya Cowsik, Zhi-Da Song +3
Using exact diagonalization, we study the projected Hamiltonian with Coulomb interaction in the 8 flat bands of first magic angle twisted bilayer graphene. Employing the U(4) (U(4)…
Twisted Bilayer Graphene V: Exact Analytic Many-Body Excitations in Twisted Bilayer Graphene Coulomb Hamiltonians: Charge Gap, Goldstone Modes and Absence of Cooper Pairing
B. Andrei Bernevig, Biao Lian, Aditya Cowsik +3
We find exact analytic expressions for the energies and wavefunctions of the charged and neutral excitations above the exact ground states (at rational filling per unit cell) of pr…
Topology-Bounded Superfluid Weight In Twisted Bilayer Graphene
Fang Xie, Zhida Song, Biao Lian +1
While regular flat bands are good for enhancing the density of states and hence the gap, they are detrimental to the superfluid weight. We show that the predicted nontrivial topolo…
The Landau Level of Fragile Topology
Biao Lian, Fang Xie, B. Andrei Bernevig
We study the Hofstadter butterfly and Landau levels of the twisted bilayer graphene (TBG). We show that the nontrivial fragile topology of the lowest two bands near the charge neut…