Single-electron acoustic charge transport on shallow-etched channels in a perpendicular magnetic field

The effect of a perpendicular magnetic field on the quantized current induc ed by a surface acoustic wave in a quasi-one-dimensional channel is studied . The channel was defined in a GaAs heterostructure by a shallow-etching te chnique. The quantized current in this constriction displayed superior prec ision (+/-60 ppm) and robustness to de bias relative to that observed previ ously in Schottky-gate-defined channels. In a perpendicular magnetic field commensurability oscillations were observed in the interval of current betw een quantized plateaus. The phase of the oscillations changes when a platea u is approached, which leads to an oscillatory change in the slope of the p lateaus.