Electron tunneling into Nb/Al multilayers and into Nb with Al overlayers

doi:10.1016/0378-4363(82)90200-5

Physica B+C

Volumes 109–110, July 1982, Pages 1775-1784

https://doi.org/10.1016/0378-4363(82)90200-5 Get rights and content

Abstract

The structure and tunneling behavior of Nb/Al multilayer films is reported. Using similar deposition methods we also show that a few monolayers of Al strongly modifies the oxidation behavior of Nb and the characteristics of tunnel junctions formed on such surfaces. This has been deduced from measurements of the oxidation rate and the tunneling characteristics over a wide voltage range with the Nb in both normal and superconducting states. The improvement in characteristics resulting from the Al overlayer allows tunneling spectroscopy of Nb without having to allow for a proximity effect on the surface.

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^∗: Permanent address: Kernforschungszentrum Karlsruhe, Inst. fur Angewandte Kernphys., Fed. Rep. Germany.

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Electron tunneling into Nb/Al multilayers and into Nb with Al overlayers

Abstract

Phys. Rev. Lett.

Phys. Rev.

J. Appl. Phys.

Modulated Structures

Phys. Rev. Lett.

Phys. Rev. Lett.

Workshop on Instrumentation for Synchrotron Radiation Research

Phys. Rev. Lett.

Phys. Rev.

Bull. Am. Phys. Soc.