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arXiv · 2408.11789

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

Oleg Grigorev·Ankur Das
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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 $\nu=2/3$. 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.

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Oleg Grigorev, Ankur Das. 2024-08-21. Fractional Quantum Hall phases of graphene beyond ultra-short range intervalley-anisotropic interaction. https://arxiv.org/abs/2408.11789

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