Imaging doubled shot noise in a Josephson scanning tunneling microscope

Article

关键词: ANDREEV REFLECTION;    CHARGE;    SUPPRESSION;   

DOI  :  10.1103/PhysRevB.100.104506

来源: SCIE

【 摘 要 】

We have imaged the current noise with atomic resolution in a Josephson scanning tunneling microscope with a Pb-Pb junction. By measuring the current noise as a function of applied bias, we reveal the change from single-electron tunneling above the superconducting gap energy to double-electron charge transfer below the gap energy when Andreev processes become dominant. Our spatially resolved noise maps show that this doubling occurs homogeneously on the surface, and also on impurity locations, demonstrating that indeed the charge pairing is not influenced by disruptions in the superconductor smaller than the superconducting coherence length.

【 授权许可】

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