Voltage-driven magnetization switching and spin pumping in Weyl semimetals

TL;DR

This paper demonstrates voltage-driven magnetization switching and spin pumping in Weyl semimetals, leveraging their unique charge-magnetization coupling due to the chiral anomaly, with potential for energy-efficient spintronics applications.

Contribution

It introduces a theoretical analysis of magnetization dynamics in Weyl semimetals driven by electric voltages, highlighting a novel, energy-efficient switching mechanism.

Findings

Magnetization can be switched by pulsed electric voltage.

Precession motion is induced by oscillating electric voltage.

The method is potentially more energy-efficient than conventional techniques.

Abstract

We demonstrate electrical magnetization switching and spin pumping in magnetically doped Weyl semimetals. The Weyl semimetal is a new class of topological semimetals, known to have nontrivial coupling between the charge and the magnetization due to the chiral anomaly. By solving the Landau-Lifshitz-Gilbert equation for a multilayer structure of a Weyl semimetal, an insulator and a metal whilst taking the charge-magnetization coupling into account, magnetization dynamics is analyzed. It is shown that the magnetization dynamics can be driven by the electric voltage. Consequently, switching of the magnetization with a pulsed electric voltage can be achieved, as well as precession motion with an applied oscillating electric voltage. The effect requires only a short voltage pulse and may therefore be more energetically efficient for us in spintronics devices compared to conventional spin transfer torque switching.