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Disorder-enabled Andreev reflection of a quantum Hall edge.

ABSTRACT: We develop a theory of charge transport along the quantum Hall edge proximitized by a superconductor. We note that generically Andreev reflection of an edge state is suppressed if translation invariance along the edge is preserved. Disorder in a "dirty" superconductor enables the Andreev reflection but makes it random. As a result, the conductance of a proximitized segment is a stochastic quantity with giant sign-alternating fluctuations and zero average. We find the statistical distribution of the conductance and its dependence on electron density, magnetic field, and temperature. Our theory provides an explanation of a recent experiment with a proximitized edge state.

SUBMITTER: Kurilovich VD

PROVIDER: S-EPMC10115825 | biostudies-literature | 2023 Apr

REPOSITORIES: biostudies-literature

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Disorder-enabled Andreev reflection of a quantum Hall edge.

Kurilovich Vladislav D VD Raines Zachary M ZM Glazman Leonid I LI

Nature communications 20230419 1

We develop a theory of charge transport along the quantum Hall edge proximitized by a superconductor. We note that generically Andreev reflection of an edge state is suppressed if translation invariance along the edge is preserved. Disorder in a "dirty" superconductor enables the Andreev reflection but makes it random. As a result, the conductance of a proximitized segment is a stochastic quantity with giant sign-alternating fluctuations and zero average. We find the statistical distribution of ...[more]

PMID: 37076501

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