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Induced superconductivity in high-mobility two-dimensional electron gas in gallium arsenide heterostructures.

ABSTRACT: Search for Majorana fermions renewed interest in semiconductor-superconductor interfaces, while a quest for higher-order non-Abelian excitations demands formation of superconducting contacts to materials with fractionalized excitations, such as a two-dimensional electron gas in a fractional quantum Hall regime. Here we report induced superconductivity in high-mobility two-dimensional electron gas in gallium arsenide heterostructures and development of highly transparent semiconductor-superconductor ohmic contacts. Supercurrent with characteristic temperature dependence of a ballistic junction has been observed across 0.6??m, a regime previously achieved only in point contacts but essential to the formation of well separated non-Abelian states. High critical fields (>16?T) in NbN contacts enables investigation of an interplay between superconductivity and strongly correlated states in a two-dimensional electron gas at high magnetic fields.

SUBMITTER: Wan Z

PROVIDER: S-EPMC4490403 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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