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Andreev reflection in engineered Al/Si/InGaAs(001) junctions

S. De Franceschi·F. Giazotto·F. Beltram·L. Sorba·M. Lazzarino·A. Franciosi
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Abstract

Complete suppression of the native n-type Schottky barrier is demonstrated in Al/InGaAs(001) junctions grown by molecular-beam-epitaxy. This result was achieved by the insertion of Si bilayers at the metal-semiconductor interface allowing the realization of truly Ohmic non-alloyed contacts in low-doped and low-In content InGaAs/Si/Al junctions. It is shown that this technique is ideally suited for the fabrication of high-transparency superconductor-semiconductor junctions. To this end magnetotransport characterization of Al/Si/InGaAs low-n-doped single junctions below the Al critical temperature is presented. Our measurements show Andreev-reflection dominated transport corresponding to junction transparency close to the theoretical limit due to Fermi-velocity mismatch

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S. De Franceschi, F. Giazotto, F. Beltram, L. Sorba, M. Lazzarino, A. Franciosi. 1999-04-22. Andreev reflection in engineered Al/Si/InGaAs(001) junctions. https://arxiv.org/abs/cond-mat/9904328

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