Magic-angle twisted bilayer graphene as a topological heavy fermion problem

ZD Song, BA Bernevig - Physical review letters, 2022 - APS
Magic-angle (θ= 1.0 5°) twisted bilayer graphene (MATBG) has shown two seemingly
contradictory characters: the localization and quantum-dot-like behavior in STM …

Pauli-limit violation and re-entrant superconductivity in moiré graphene

Y Cao, JM Park, K Watanabe, T Taniguchi… - Nature, 2021 - nature.com
Moiré quantum matter has emerged as a materials platform in which correlated and
topological phases can be explored with unprecedented control. Among them, magic-angle …

Quantum textures of the many-body wavefunctions in magic-angle graphene

KP Nuckolls, RL Lee, M Oh, D Wong, T Soejima… - Nature, 2023 - nature.com
Interactions among electrons create novel many-body quantum phases of matter with
wavefunctions that reflect electronic correlation effects, broken symmetries and collective …

Twisted bilayer graphene. IV. Exact insulator ground states and phase diagram

B Lian, ZD Song, N Regnault, DK Efetov, A Yazdani… - Physical Review B, 2021 - APS
We derive the exact insulator ground states of the projected Hamiltonian of magic-angle
twisted bilayer graphene (TBG) flat bands with Coulomb interactions in various limits, and …

Deconfined quantum critical points: a review

T Senthil - arXiv preprint arXiv:2306.12638, 2023 - arxiv.org
Continuous phase transitions in equilibrium statistical mechanics were successfully
described 50 years ago with the development of the renormalization group framework. This …

Twisted bilayer graphene. III. Interacting Hamiltonian and exact symmetries

BA Bernevig, ZD Song, N Regnault, B Lian - Physical Review B, 2021 - APS
We derive the explicit Hamiltonian of twisted bilayer graphene (TBG) with Coulomb
interaction projected into the flat bands and study the symmetries of the Hamiltonian. First …

Twisted bilayer graphene. V. Exact analytic many-body excitations in Coulomb Hamiltonians: Charge gap, Goldstone modes, and absence of Cooper pairing

BA Bernevig, B Lian, A Cowsik, F Xie, N Regnault… - Physical Review B, 2021 - APS
We find exact analytic expressions for the energies and wave functions of the charged and
neutral excitations above the exact ground states (at rational filling per unit cell) of projected …

Theory of zero-field superconducting diode effect in twisted trilayer graphene

HD Scammell, JIA Li, MS Scheurer - 2D Materials, 2022 - iopscience.iop.org
In a recent experiment (Lin et al 2021 arXiv: 2112.07841 [cond-mat. str-el]), the
superconducting phase hosted by a heterostructure of mirror-symmetric twisted trilayer …

Kondo lattice model of magic-angle twisted-bilayer graphene: Hund's rule, local-moment fluctuations, and low-energy effective theory

H Hu, BA Bernevig, AM Tsvelik - Physical review letters, 2023 - APS
We apply a generalized Schrieffer-Wolff transformation to the extended Anderson-like
topological heavy fermion (THF) model for the magic-angle (θ= 1.0 5°) twisted bilayer …

Twisted bilayer graphene. VI. An exact diagonalization study at nonzero integer filling

F Xie, A Cowsik, ZD Song, B Lian, BA Bernevig… - Physical Review B, 2021 - APS
Using exact diagonalization, we study the projected Hamiltonian with the Coulomb
interaction in the eight flat bands of first magic angle twisted bilayer graphene. Employing …