Kato Yoshihiro D, Okamura Yoshihiro, Hirschberger Max, Tokura Yoshinori, Takahashi Youtarou
Department of Applied Physics and Quantum Phase Electronics Center, University of Tokyo, Tokyo, 113-8656, Japan.
RIKEN Center for Emergent Matter Science (CEMS), Wako, 351-0198, Japan.
Nat Commun. 2023 Sep 5;14(1):5416. doi: 10.1038/s41467-023-41203-y.
The magnetic skyrmion is a spin-swirling topological object characterized by its nontrivial winding number, holding potential for next-generation spintronic devices. While optical readout has become increasingly important towards the high integration and ultrafast operation of those devices, the optical response of skyrmions has remained elusive. Here, we show the magneto-optical Kerr effect (MOKE) induced by the skyrmion formation, i.e., topological MOKE, in GdPdSi. The significantly enhanced optical rotation found in the skyrmion phase demonstrates the emergence of topological MOKE, exemplifying the light-skyrmion interaction arising from the emergent gauge field. This gauge field in momentum space causes a dramatic reconstruction of the electronic band structure, giving rise to magneto-optical activity ranging up to the sub-eV region. The present findings pave a way for photonic technology based on skyrmionics.
磁斯格明子是一种自旋涡旋的拓扑对象，其特征在于具有非平凡的缠绕数，在下一代自旋电子器件方面具有潜力。虽然光学读出对于这些器件的高集成度和超快运行变得越来越重要，但斯格明子的光学响应仍然难以捉摸。在此，我们展示了在GdPdSi中由斯格明子形成诱导的磁光克尔效应（MOKE），即拓扑MOKE。在斯格明子相中发现的显著增强的旋光性证明了拓扑MOKE的出现，例证了由涌现规范场引起的光-斯格明子相互作用。动量空间中的这种规范场导致电子能带结构的剧烈重构，产生高达亚电子伏特区域的磁光活性。目前的发现为基于斯格明子学的光子技术铺平了道路。
