Quantum wire fabrication from compensating-layer GaAs–AlGaAs heterostructures

Abstract

Abstract Nanoscale devices are fabricated from modulation-doped GaAs–AlGaAs heterostructures, where the two-dimensional electron system is initially depleted. Upon removing the p-type capping layer that compensates for the n-type supply layer the electron system is induced. Quantum wire structures and conducting areas as leads are formed by patterning a thin resist layer with an atomic force microscope and subsequent selective wet etching. At T=4.2 K the electrical characteristics of a quantum point contact and a 250-nm long quantum wire exhibit quantized ballistic conductance.