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arXiv · 2309.14411

Signatures of Parafermion Zero Modes in Fractional Quantum Hall-Superconductor Heterostructures

Junyi Cao·Angela Kou·Eduardo Fradkin
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Abstract

Parafermion zero modes can arise in hybrid structures composed of $\nu=1/m$ fractional quantum Hall edges proximitized with an s-wave superconductor. Here we consider parafermion and Cooper pair tunneling, and backscattering in a junction formed in such hybrid structures. We find that the $4\pi m$ periodicity due to parafermion-only tunneling reduces, in the presence of backscattering, to $4\pi$-periodic at zero temperature and $2\pi$-periodic at finite temperature unless the fermion parity is fixed. Nevertheless, a clear signature of parafermion tunneling remains in the shape of the current-phase relation.

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Junyi Cao, Angela Kou, Eduardo Fradkin. 2023-09-25. Signatures of Parafermion Zero Modes in Fractional Quantum Hall-Superconductor Heterostructures. https://doi.org/10.1103/physrevb.109.l161106

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