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arXiv · 2212.01706

Fractional quantum Hall effect with unconventional pairing in monolayer graphene

Anirban Sharma·Songyang Pu·Ajit C. Balram·Jainendra K. Jain
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Abstract

Motivated by the observation of even denominator fractional quantum Hall effect in the $n=3$ Landau level of monolayer graphene [Y. Kim $\textit{et al.}$, Nature Physics $\textbf{15}$, 154 (2019)], we consider a Bardeen-Cooper-Schrieffer variational state for composite fermions and find that the composite-fermion Fermi sea in this Landau level is unstable to an $f$-wave pairing. Analogous calculation suggests the possibility of a $p$-wave pairing of composite fermions at half filling in the $n=2$ graphene Landau level, whereas no pairing instability is found at half filling in the $n=0$ and $1$ graphene Landau levels. The relevance of these results to experiments is discussed.

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Anirban Sharma, Songyang Pu, Ajit C. Balram, Jainendra K. Jain. 2022-12-03. Fractional quantum Hall effect with unconventional pairing in monolayer graphene. https://doi.org/10.1103/physrevlett.130.126201

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