Crossover from tunneling to meta.llic behavior in superconductofgsemiconductor contacts
نویسندگان
چکیده
We describe current-voltage measurements on superconducting Nb/lnGaAs junction field-effect transistors which reveal a crossover from tunneling-dominated to Andreev scattering-dominated transport at the superconductor-semiconductor contacts as Schottky barrier thickness decreases with increasing interfacial dopant concentration. These measurements are the first demonstration of such a crossover in a thin-film structure, and are of interest for investigations of hybrid superconductor-semiconductor devices, proximity effect boundary conditions, and transport in ohmic contacts to semiconductors.
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