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Tuning locality of pair coherence in graphene-based Andreev interferometers.

ABSTRACT: We report on gate-tuned locality of superconductivity-induced phase-coherent magnetoconductance oscillations in a graphene-based Andreev interferometer, consisting of a T-shaped graphene bar in contact with a superconducting Al loop. The conductance oscillations arose from the flux change through the superconducting Al loop, with gate-dependent Fraunhofer-type modulation of the envelope. We confirm a transitional change in the character of the pair coherence, between local and nonlocal, in the same device as the effective length-to-width ratio of the device was modulated by tuning the pair-coherence length ?T in the graphene layer.

SUBMITTER: Kim M

PROVIDER: S-EPMC4348647 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Tuning locality of pair coherence in graphene-based Andreev interferometers.

Kim Minsoo M Jeong Dongchan D Lee Gil-Ho GH Shin Yun-Sok YS Lee Hyun-Woo HW Lee Hu-Jong HJ

Scientific reports 20150304

We report on gate-tuned locality of superconductivity-induced phase-coherent magnetoconductance oscillations in a graphene-based Andreev interferometer, consisting of a T-shaped graphene bar in contact with a superconducting Al loop. The conductance oscillations arose from the flux change through the superconducting Al loop, with gate-dependent Fraunhofer-type modulation of the envelope. We confirm a transitional change in the character of the pair coherence, between local and nonlocal, in the s ...[more]

PMID: 25737106

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