Evidence of two-electron tunneling interference in Nb/InAs junctions
نویسندگان
چکیده
The impact of junction transparency in driving phase-coherent charge transfer across diffusive semiconductor-superconductor junctions is demonstrated. We present conductivity data for a set of Nb-InAs junctions differing only in interface transparency. Our experimental findings are analyzed within the quasi-classical Green-function approach and unambiguously show the physical processes giving rise to the observed excess zero-bias conductivity. PACS numbers: 74.80.Fp, 73.23.Ad, 73.40.Qv
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