Large band-splitting in $g$-wave type altermagnet CrSb

TL;DR

This study uncovers large $g$-wave band splitting in the altermagnetic material CrSb, combining experimental and theoretical methods to reveal its electronic structure and potential for spintronics applications.

Contribution

It provides the first detailed mapping of CrSb's three-dimensional electronic structure and confirms its unique $g$-wave symmetry with record spin splitting magnitude.

Findings

Spin splitting reaches 0.93 eV near $E_F$

CrSb exhibits $g$-wave symmetry in its electronic structure

CrSb's properties make it promising for spintronics

Abstract

Altermagnetism (AM), a newly discovered magnetic state, ingeniously integrates the properties of ferromagnetism and antiferromagnetism, representing a significant breakthrough in the field of magnetic materials. Despite experimental verification of some typical AM materials, such as MnTe and MnTe$_2$, the pursuit of AM materials that feature larger spin splitting and higher transition temperature is still essential. Here, our research focuses on CrSb, which possesses N{\'e}el temperature of up to 700K and giant spin splitting near the Fermi level ($E_F$). Utilizing high-resolution angle-resolved photoemission spectroscopy and density functional theory calculations, we meticulously map the three-dimensional electronic structure of CrSb. Our photoemission spectroscopic results on both (0001) and (10$\overline{1}$0) cleavages of CrSb collaboratively reveal unprecedented details on AM-induced band splitting, and subsequently pin down its unique bulk $g$-wave symmetry through quantitative analysis of the angular and photon-energy dependence of spin splitting. Moreover, the observed spin splitting reaches the magnitude of 0.93~eV near $E_F$, the most substantial among all confirmed AM materials. This study not only validates the nature of CrSb as a prototype $g$-wave like AM material but also underscores its pivotal role in pioneering applications in spintronics.