[22p-E205-1~16] 10.1 新物質・新機能創成（作製・評価技術）

▼ [22p-E205-5] Observation of spontaneous x-ray magnetic circular dichroism in the antiferromagnetic Mn₃Sn thin film

〇Shoya Sakamoto¹、Tomoya Higo²、Masanobu Shiga¹、Kenta Amemiya³、Satoru Nakatsuji^1,2,4,5、Shinji Miwa^1,4 (1.ISSP, Univ. of Tokyo、2.Phys. Dept., Univ. of Tokyo、3.IMSS, KEK、4.TQSI, Univ. of Tokyo、5.JHU)

キーワード：Mn3Sn, XMCD, Antiferromagnetism

X-ray magnetic circular dichroism (XMCD) is usually inapplicable to antiferromagnets in the absence of external magnetic fields. However, it was recently proposed that the inverse triangular spin structure (or the ferroic order of cluster magnetic octupole) of a noncollinear antiferromagnet can induce finite XMCD signals. To test this proposal, we performed XMCD measurements on an epitaxial Mn₃Sn (1-100) thin film prepared by molecular beam epitaxy.
We observed finite XMCD signals even when magnetic fields were sufficiently weak (0.1 T). Because the spectral line shape is distinct from that taken with stronger magnetic fields (5 T), we conclude that the XMCD spectra taken with 0.1 and 5 T predominantly reflect the inverse triangular spin structure and spin canting, respectively.