Quantized charge pumping by surface acoustic waves in ballistic quasi-1D channels

TL;DR

This paper models how surface acoustic waves induce quantized charge pumping in ballistic quasi-one-dimensional channels, revealing the role of transmission resonances and controllable parameters in current quantization.

Contribution

It introduces an exactly solvable tight-binding model for non-interacting electrons to analyze acoustoelectric current quantization in quantum channels.

Findings

Current quantization is linked to transmission resonances.

Controllable parameters affect the plateau structure.

Results align with experimental data.

Abstract

Adiabatic pumping of electrons induced by surface acoustic waves (SAWs) in a ballistic quasi-1D quantum channel is considered using an exactly solvable tight-binding model for non-interacting electrons. The single-electron degrees of freedom, responsible for acoustoelectric current quantization, are related to the transmission resonances. We study the influence of experimentally controllable parameters (SAW power, gate voltage, source-drain bias, amplitude and phase of a secondary SAW beam) on the plateau-like structure of the acoustoelectric current. The results are consistent with existing experimental observations.