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arXiv · 2301.04169

Signatures of Supersymmetry in the $ν{=}5/2$ Fractional Quantum Hall Effect

Abstract

The Moore-Read state, one of the leading candidates for describing the fractional quantum Hall effect at filling factor $ν{=}5/2$, is a paradigmatic $p$-wave superconductor with non-Abelian topological order. Among its many exotic properties, the state hosts two collective modes: a bosonic density wave and a neutral fermion mode that arises from an unpaired electron in the condensate. It has recently been proposed that the descriptions of the two modes can be unified by postulating supersymmetry (SUSY) that relates them in the long-wavelength limit. Here we extend the SUSY description to construct wave functions of the two modes on closed surfaces, such as the sphere and torus, and we test the resulting states in large-scale numerical simulations. We demonstrate the equivalence in the long-wavelength limit between SUSY wave functions and previous descriptions of collective modes based on the Girvin-MacDonald-Platzman ansatz, Jack polynomials, and bipartite composite fermions. Leveraging the first-quantized form of the SUSY wave functions, we study their energies using the Monte Carlo method and show that realistic $ν{=}5/2$ systems are close to the putative SUSY point, where the two collective modes become degenerate in energy.

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Songyang Pu, Ajit C. Balram, Mikael Fremling, Andrey Gromov, Zlatko Papić. 2023-05-07. Signatures of Supersymmetry in the $ν{=}5/2$ Fractional Quantum Hall Effect. https://doi.org/10.1103/physrevlett.130.176501

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