Single-parameter nonadiabatic quantized charge pumping

Abstract

Controlled charge pumping in an $\mathrm{Al}\mathrm{Ga}\mathrm{As}∕\mathrm{Ga}\mathrm{As}$ gated nanowire by single-parameter modulation is experimentally and theoretically studied. Transfer of integral multiples of the elementary charge per modulation cycle is clearly demonstrated. A simple theoretical model shows that such a quantized current can be generated via loading and unloading of a dynamic quasibound state. It demonstrates that nonadiabatic blockade of unwanted tunnel events can obliterate the requirement of having at least two phase-shifted periodic signals to realize quantized pumping.