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Observation of enhanced superconductivity in the vicinity of Ar-induced nano-cavities in Pb(111).

ABSTRACT: Local variations of superconductivity have been studied using scanning tunneling microscopy around nano-cavities formed by Ar ions embedded in Pb(111). Various factors including the density of states at Fermi energy, electron-phonon couplings, and quantum well states, which are known to affect superconductivity, have been examined. We show that the superconductivity is enhanced near the nano-cavities and propose that quantum effects such as quantum confinement, proximity effect and multi-gap effect are possibly involved in determining the superconducting gap of this system. These results have important implications for the characterization and understanding of superconductivity at a nanometer scale.

SUBMITTER: Song SY

PROVIDER: S-EPMC5610268 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Observation of enhanced superconductivity in the vicinity of Ar-induced nano-cavities in Pb(111).

Song Sang Yong SY Seo Jungpil J

Scientific reports 20170922 1

Local variations of superconductivity have been studied using scanning tunneling microscopy around nano-cavities formed by Ar ions embedded in Pb(111). Various factors including the density of states at Fermi energy, electron-phonon couplings, and quantum well states, which are known to affect superconductivity, have been examined. We show that the superconductivity is enhanced near the nano-cavities and propose that quantum effects such as quantum confinement, proximity effect and multi-gap eff ...[more]

PMID: 28939806

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