Wang Dinghui, Wang Huaiqiang, Liu Lulu, Zhang Junting, Zhang Haijun
School of Materials Science and Physics, China University of Mining and Technology, Xuzhou 221116, China.
Center for Quantum Transport and Thermal Energy Science, School of Physics and Technology, Nanjing Normal University, Nanjing 210023, China.
Nano Lett. 2025 Jan 8;25(1):498-503. doi: 10.1021/acs.nanolett.4c05384. Epub 2024 Dec 16.
Altermagnetism, as a recently discovered unconventional antiferromagnetism, allows the lifting of spin degeneracy without net magnetization. The spin splitting of the intrinsic altermagnets is protected by the spin space group symmetry and is therefore difficult to control externally. Here, we propose an extrinsic altermagnet as a complement to the intrinsic altermagnet, whose spin splitting is induced by and can be significantly modulated by the electric field. We then screened intrinsic and extrinsic altermagnets by combining symmetry analysis and high-throughput calculations, identifying 16 intrinsic altermagnets and 24 extrinsic altermagnets. We demonstrate that the spin splitting of extrinsic altermagnets is proportional to the electric field strength, and its sign can be switched by reversing the electric field. Some extrinsic altermagnets exhibit considerable spin splitting, such as CaMnSi with 398 meV under an electric field of 0.1 V/Å. This work provides a realistic material platform for the potential application of 2D altermagnets.
交替磁性作为一种最近发现的非常规反铁磁性，能够在无净磁化的情况下解除自旋简并。本征交替磁体的自旋分裂由自旋空间群对称性保护，因此难以通过外部手段进行控制。在此，我们提出一种非本征交替磁体作为本征交替磁体的补充，其自旋分裂由电场诱导且可被电场显著调制。然后，我们通过结合对称性分析和高通量计算筛选本征和非本征交替磁体，识别出16种本征交替磁体和24种非本征交替磁体。我们证明非本征交替磁体的自旋分裂与电场强度成正比，并且其符号可以通过反转电场来切换。一些非本征交替磁体表现出相当大的自旋分裂，例如在0.1 V/Å的电场下，CaMnSi的自旋分裂为398 meV。这项工作为二维交替磁体的潜在应用提供了一个现实的材料平台。
