Fabrication of quantum wires in thermally etched V-grooves by molecular beam epitaxy

Abstract

Quasi-one-dimensional quantum wires have been formed in V-grooves on GaAs substrates. A new fabrication technique based on in situ thermal etching of masked substrates and subsequent overgrowth by molecular beam epitaxy has been developed. The device geometries enabled formation of low-resistance ohmic contacts. Two-terminal magnetoresistance measurements of single-wire devices show transport qualities previously not witnessed in growth on non-planar substrates. Illumination has been used to modulate the carrier density and lateral potential profile of the wires.