Topological charge pumping effect by the magnetization dynamics on the Surface of Three-Dimensional Topological Insulators

TL;DR

This paper demonstrates that magnetization precession on the surface of a 3D topological insulator induces a topologically protected charge current, showcasing a robust rectification effect due to quantum anomaly.

Contribution

It introduces a novel topological charge pumping mechanism driven by magnetization dynamics on topological insulator surfaces.

Findings

Magnetization precession induces a direct charge current.

The rectification effect is topologically protected.

The effect is robust against impurities and exchange field variations.

Abstract

We discuss a current dynamics on the surface of a 3-dimensional topological insulator induced by magnetization precession of a ferromagnet attached. It is found that the magnetization dynamics generates a direct charge current when the precession axis is within the surface plane. This rectification effect is due to a quantum anomaly and is topologically protected. The robustness of the rectification effect against first-varying exchange field and impurities is confirmed by explicit calculation.