English

Fractional Quantum Hall phases of graphene beyond ultra-short range intervalley-anisotropic interaction

Mesoscale and Nanoscale Physics 2025-01-28 v2 Strongly Correlated Electrons

Abstract

Recent experimental and theoretical development in the Quantum Hall effect in monolayer graphene showed that the previous model of the valley-anisotropy interaction is incomplete, as it was assumed to be ultra-short range (USR). In this work, we use exact diagonalization to go beyond the ultra-short range to find the different phases for ν=2/3\nu=2/3. We model the interaction as Yukawa so that we can control the range as a proof of concept. Even in this simple setting, we discovered how dropping the USR condition shifts the transition borders in favour of certain phases, leads to a new bond-ordered phase appearing, and breaks the ferromagnetic phase in two competing states as a result of lifting the USR-driven degeneracy.

Keywords

Cite

@article{arxiv.2408.11789,
  title  = {Fractional Quantum Hall phases of graphene beyond ultra-short range intervalley-anisotropic interaction},
  author = {Oleg Grigorev and Ankur Das},
  journal= {arXiv preprint arXiv:2408.11789},
  year   = {2025}
}

Comments

17 pages and 6 figures 1 table