Various electronic crystal phases in rhombohedral graphene multilayers

TL;DR

This paper explores various electron crystal phases in rhombohedral multilayer graphene, revealing a cascade of phase transitions, topological states with Chern numbers, and potential quantum anomalous Hall effects through advanced calculations.

Contribution

It introduces a comprehensive theoretical analysis of electron crystal phases and topological states in rhombohedral graphene multilayers, including pressure effects and experimental signatures.

Findings

Discovery of a cascade sequence of phase transitions with increasing carrier density.

Identification of electron crystal phases with non-zero Chern numbers and quantum anomalous Hall effect.

Characterization of pressure-driven phase transitions and thermodynamic signatures.

Abstract

We systematically investigate the emergence of electron crystal phases in rhombohedral multilayer graphene using comprehensive self-consistent Hartree Fock calculations combined with \textit{ab initio} tight binding model. As the carrier density increases, we uncover an isospin cascade sequence of phase transitions that gives rise to a rich variety of ordered states, including electron crystal phases with non-zero Chern numbers. We further show the nearly degeneracy of these topological electron crystals hosting extended quantum anomalous Hall effect (EQAH) in the mean field regime and characterize pressure driven phase transitions. Finally, we discuss the thermodynamic signatures, particularly the behavior of the inverse compressibility, in light of recent experimental observations.