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arXiv · 2308.11180

Broken Kramers' degeneracy in altermagnetic MnTe

Suyoung Lee·Sangjae Lee·Saegyeol Jung·Jiwon Jung·Donghan Kim·Yeonjae Lee·Byeongjun Seok·Jaeyoung Kim·Byeong Gyu Park·Libor Šmejkal·Chang-Jong Kang·Changyoung Kim
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Abstract

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 $in~situ$ angle-resolved photoemission spectroscopy, we report the electronic structure of an altermagnetic candidate, $\alpha$-MnTe. Temperature dependent study reveals the lifting of Kramers{\textquoteright} degeneracy accompanied by a magnetic phase transition at $T_N=267\text{ K}$ with spin splitting of up to $370\text{ meV}$, providing direct spectroscopic evidence for altermagnetism in MnTe.

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Suyoung Lee, Sangjae Lee, Saegyeol Jung, Jiwon Jung, Donghan Kim, Yeonjae Lee, Byeongjun Seok, Jaeyoung Kim, Byeong Gyu Park, Libor Šmejkal, Chang-Jong Kang, Changyoung Kim. 2023-08-22. Broken Kramers' degeneracy in altermagnetic MnTe. https://doi.org/10.1103/physrevlett.132.036702

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