Altermagnetism is a newly identified fundamental class of magnetism with vanishing net magnetization and time-reversal symmetry broken electronic structure. Probing the unusual electronic structure with nonrelativistic spin splitting would be a direct experimental verification of altermagnetic phase. By combining high-quality film growth and insitu angle-resolved photoemission spectroscopy, we report the electronic structure of an altermagnetic candidate, α-MnTe. Temperature dependent study reveals the lifting of Kramers{\textquoteright} degeneracy accompanied by a magnetic phase transition at TN=267 K with spin splitting of up to 370 meV, providing direct spectroscopic evidence for altermagnetism in MnTe.
@article{arxiv.2308.11180,
title = {Broken Kramers' degeneracy in altermagnetic MnTe},
author = {Suyoung Lee and Sangjae Lee and Saegyeol Jung and Jiwon Jung and Donghan Kim and Yeonjae Lee and Byeongjun Seok and Jaeyoung Kim and Byeong Gyu Park and Libor Šmejkal and Chang-Jong Kang and Changyoung Kim},
journal= {arXiv preprint arXiv:2308.11180},
year = {2024}
}