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arXiv · 1109.5038

Normal reflection at superconductor - normal metal interfaces due to Fermi surface mismatch

Elina Tuuli·Kurt Gloos
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Abstract

Electrons can be reflected at an interface between two metals because of a dielectric barrier or different properties of the Fermi surface. Andreev reflection allows to directly measure normal reflection when one of the metals is a superconductor. We have investigated normal reflection at interfaces between non-magnetic normal metals and superconducting Nb (Tc = 9.2 K) and Al (Tc = 1.2 K). The distribution of the values of the relative strength of the interface barrier, Z, for a number of contacts of a specific metal combination shows a well-defined peak which can be attributed to Fermi surface mismatch. Our reflection coefficients are generally smaller than those predicted theoretically or those derived from proximity-effect studies of normal-superconductor bi-layers.

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Elina Tuuli, Kurt Gloos. 2011-09-23. Normal reflection at superconductor - normal metal interfaces due to Fermi surface mismatch. https://doi.org/10.1088/1742-6596/400/4/042066

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