Altermagnetic Spin Precession and Spin Transistor

TL;DR

This paper explores the spin dynamics and transport properties of altermagnets, demonstrating their potential for spintronic devices through spin precession and a prototype spin transistor based on a $d$-wave altermagnet.

Contribution

It introduces a novel quantum transport setup for altermagnets, revealing spin precession effects and proposing a highly efficient, electrically tunable spin transistor.

Findings

Altermagnetic spin splitting causes observable spin precession patterns.

The transverse Hall-like voltage oscillates with a period indicating spin-splitting strength.

The proposed spin transistor is robust against dephasing and crystalline warping.

Abstract

Altermagnets hold great potential for spintronic applications, yet their intrinsic spin dynamics and associated transport properties remain largely unexplored. Here, we investigate spin-resolved quantum transport in a multi-terminal setup based on a $d$-wave altermagnet. It is found that the altermagnetic spin splitting in momentum space induces an interesting spin precession in two-dimensional real space, giving rise to characteristic spin patterns. This altermagnetic spin precession manifests as a spatial modulation of the transverse Hall-like voltage, whose oscillation period provides a direct measure of the spin-splitting strength. When the altermagnetism is electrically tunable, the proposed setup functions as a prototype for a highly efficient spin transistor. The key physical effects are shown to be robust against dephasing and crystalline warping. Our work not only identifies a fingerprint signature of altermagnets, offering a direct probe of the altermagnetic spin splitting, but also represents an important step toward bridging their fundamental physics with practical spintronic applications.