One dimensional electron transport and drain current quantization at 77 K in InAs heterojunction quantum wires

The authors have fabricated quantum wires on the InAs/AlGaSb heterostructure by utilizing electron beam lithography and wet-chemical etching. The electron confinement into quasi-one-dimensional freedom of motion was verified by magnetoresistance measurement at 4.2 K. In two terminal devices with extremely narrow channel structure, quantized drain current through drain-induced barrier lowering has been observed at 77 K. Coulomb oscillations and Coulomb staircases were seen to overlap with staircase u characteristics reflecting the small parasitic capacitance between terminals. Material, structural, and temperature effects on these devices were examined. >