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

▼ [22p-E205-4] Observation of non-collinear antiferromagnetic domain structure in epitaxial Mn₃Sn thin films

〇(M1)Tomohiro Uchimura^1,2、Ju-Young Yoon^1,2、Yuma Sato^1,3、Yutaro Takeuchi⁴、Shun Kanai^1,5,6,7,8、Ryota Takechi^1,2、Keisuke Kishi^1,2、Yuta Yamane^1,9、Samik DuttaGupta^1,6,7、Jun'ichi Ieda¹⁰、Hideo Ohno^{1,2,3,4,6,7,11}、Shunsuke Fukami^{1,2,3,4,6,7,11} (1.Laboratory for Nanoelectronics and Spintronics, RIEC, Tohoku Univ.、2.Graduate School of Engineering, Tohoku Univ.、3.School of Engineering, Tohoku Univ.、4.WPI-AIMR, Tohoku Univ.、5.DEFS, Tohoku Univ.、6.CSRN, Tohoku Univ.、7.CSIS, Tohoku Univ.、8.PRESTO, JST、9.FRIS, Tohoku Univ.、10.ASRC, JAEA、11.CIES, Tohoku Univ.)

キーワード：spintronics, non-collinear antiferromagnet, magneto-optical Kerr effect

Non-collinear antiferromagnetic D0₁₉-Mn₃Sn has recently attracted increasing attention in spintronics owing to its topologically nontrivial phenomena. Here, we observe domain structures of (1-100)-oriented Mn₃Sn thin films with various compositions using MOKE, and discuss on the reversal process and its consequences. From MOKE images, the domain structures reversed by external magnetic field is observed. In addition, we find that the reversal starts with a nucleation of domains dispersed in the film, followed by an anisotropic propagation of domain wall. We also find that the amplitude of the Kerr rotation angle varies with the composition of Mn-Sn, and the result is consistent with the reversible area revealed from the domain observation. Furthermore, the structural analysis indicates that the observed composition dependence can be attributed to formations of grains with different crystalline phases or crystallographic orientations. Our study provides a basic magneto-optical properties for the exploration of unraveled unique properties of non-collinear antiferromagnets.