Andreev reflection in Si-engineered Al/InGaAs hybrid junctions
نویسندگان
چکیده
Andreev-reflection dominated transport is demonstrated in Al/nIn0.38Ga0.62As superconductor-semiconductor junctions grown by molecularbeam epitaxy on GaAs(001). High junction transparency was achieved in low-doped devices by exploiting Si interface bilayers to suppress the native Schottky barrier. It is argued that this technique is ideally suited for the fabrication of ballistic transport hybrid microstructures. Typeset using REVTEX a)Also with Istituto ICMAT-CNR, Via Salaria km 29.3, I-00016 Monterotondo, Italy. b)Also with Università di Trieste, Trieste, Italy.
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Andreev reflection in engineered Al/Si/InGaAs(001) junctions
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 lowdoped and low-In content InGaAs/Si/Al junctions. It is shown that this technique is ideally suited f...
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