Two-Dimensional Spin-Antiferroelectric Altermagnets with Giant Spin Splitting: From Model to Material Realization

TL;DR

This paper introduces a new class of 2D multiferroic altermagnets with giant spin splitting, demonstrating their potential for electrically controlled spintronic applications through theoretical design and material prediction.

Contribution

The authors propose a general design strategy for 2D spin-AFEAMs and predict specific monolayer materials, advancing the development of electrically switchable spintronic devices.

Findings

Predicted monolayer $( ext{CoCl})_2 ext{Te}$ as a candidate 2D spin-AFEAM.

Demonstrated tunable spin current switching via electric field angle and gate polarity.

Enriched the family of 2D multiferroics with potential for high-performance spintronics.

Abstract

The realization of multiferroic altermagnets featuring giant intrinsic spin splitting, hold great promise for next-generation spintronics. In this work, based on the recently proposed concept of spin-antiferroelectric (spin-AFE), we construct a class of two-dimensional (2D) multiferroic altermagnets, termed 2D spin-antiferroelectric altermagnets (2D spin-AFEAMs), enabling electrical control of spin polarization via a gate field. Furthermore, we propose a general design strategy for constructing 2D spin-AFEAMs with large intrinsic spin splitting. Guided by this strategy, we predict monolayer $(\mathrm{CoCl})_2\mathrm{Te}$ and its family materials as potential candidates of 2D spin-AFEAM. We uncover a highly tunable transport regime in monolayer $(\mathrm{CoCl})_2\mathrm{Te}$, where the spin current can be switched via the in-plane electric field angle when hole-doped, and via the gate field polarity when electron-doped. Our work enriches the family of 2D multiferroics and provides a blueprint for realizing high-performance, electrically switchable altermagnetic spintronic devices.