A topological quantum pump in serpentine-shaped semiconducting narrow channels

TL;DR

This paper proposes a novel topological charge pump using a serpentine-shaped semiconducting channel with Rashba spin-orbit interaction and a rotating magnetic field, enabling precise charge transport without oscillating voltages.

Contribution

It introduces a new topological quantum pump design leveraging geometric curvature and magnetic fields, expanding the methods for quantum charge pumping.

Findings

The system achieves quantized charge pumping without oscillating voltages.

The geometric curvature modulates Rashba spin-orbit interaction to enable topological pumping.

Potential applications in quantum metrology are identified.

Abstract

We propose and analyze theoretically a one-dimensional solid-state electronic setup that operates as a topological charge pump in the complete absence of superimposed oscillating local voltages. The system consists of a semiconducting narrow channel with strong Rashba spin-orbit interaction patterned in a mesoscale serpentine shape. A rotating planar magnetic field serves as the external ac perturbation, and cooperates with the Rashba spin-orbit interaction, which is modulated by the geometric curvature of the electronic channel to realize the topological pumping protocol originally introduced by Thouless in an entirely novel fashion. We expect the precise pumping of electric charges in our mesoscopic quantum device to be relevant for quantum metrology purposes.