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arXiv · 2609.02976

Valley polarization dependence of candidate even-denominator fractional quantum Hall states in monolayer graphene

Saswata Sahu·Amarendra Pr. Indra·Moumita Indra
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Abstract

We investigate even-denominator fractional quantum Hall (EDFQH) states in monolayer graphene, focusing on the experimentally observed filling fractions $\nu = 1/2$ and $\nu = 1/4$. Owing to the approximate SU(4) symmetry arising from spin and valley degrees of freedom, graphene hosts a rich variety of multi-component fractional quantum Hall states with different polarization configurations. Using the Chern-Simons composite fermion framework for SU(4) systems, we construct candidate variational wave functions corresponding to distinct spin, valley, and mixed polarization states. The ground-state energies of these states are evaluated numerically using the Coulomb interaction in spherical geometry. By comparing energies across different polarization sectors, we identify the energetically favored configurations at $\nu = 1/2$ and $\nu = 1/4$. Our variational energy comparison suggests that the energetically favored candidate states correspond to multi-component correlated quantum Hall liquids. Within the restricted family of trial states considered here, these states differ from a simple composite-fermion Fermi-sea description. These findings provide insight into the role of valley polarization and SU(4) symmetry in stabilizing even-denominator fractional quantum Hall states in graphene.

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Saswata Sahu, Amarendra Pr. Indra, Moumita Indra. 2026-09-02. Valley polarization dependence of candidate even-denominator fractional quantum Hall states in monolayer graphene. https://doi.org/10.1209/0295-5075%2Fae9791

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