2026-09-16 早稲田大学
磁性体薄膜中の磁気スキルミオンに光のスキルミオンを照射した時に生じる「回転」、「スキップ」、「トロコイド旋回」と呼ばれる特徴的な運動の概念図。回転運動では、磁気スキルミオンが光の中心の周囲を回る。スキップ運動では、円軌道を運動していた磁気スキルミオンが特定の場所で急に軌道を変える。さらに、条件によっては小さなループを繰り返しながら進むトロコイド旋回運動が現れる。
＜関連情報＞
- https://www.waseda.jp/inst/research/news/85820
- https://journals.aps.org/prl/abstract/10.1103/hylp-trxp
磁気スキルミオンと光学スキルミオンの相互作用 Magnetic Skyrmion Interacting with Optical Skyrmion
Lan Bo, Jian Chen, Xichao Zhang, Yan Zhou, Chengwei Qiu, and Masahito Mochizuki
Physical Review Letters Published: 14 September, 2026
DOI: https://doi.org/10.1103/hylp-trxp
Abstract
Magnetic skyrmions (MSks) and optical skyrmions (OSks) embody topology in matter and in light, respectively. Here we investigate the interaction between a single MSk and an OSk beam. Three distinct nonlinear dynamical modes are identified: rotation, skipping, and trochoidal motion. By decomposing the optical driving force into gradient, orbital-angular-momentum, and spin-angular-momentum contributions, we clarify their respective roles of radial confinement, azimuthal drift, and precessional modulation. The skipping motion arises from the azimuthal asymmetry of the OSk beam and exhibits spatial selectivity originating from the magnetization-polarization coupling between the MSk and OSk. In three dimensions, the coupling acquires a propagation-dependent phase dominated by the differential Gouy phase, which yields -asymmetric skipping trajectories. These results bridge topological particles and topological fields within a unified framework, offering helicity-selective and phase-programmable routes to optomagnonic control.
