Continuing our investigations on the interplay between spin wave and magnetic texture, we proceed to simplify their interplay by treating both the magnetic texture and spin wave as particle-like objects, and their interaction becomes a particle-colliding process.
In magnetic system, spin wave and magnetic texture can be regarded as two types of elementary excitations with fast and slow dynamics upon homogenous background. Understanding their interaction lies in the heart of our pursuit of constructing purely magnetic logic devices.
A powerful tool to describe the dynamics of the soft objects is the collective coordinate method, which focuses on the primary dynamics and ignores the minor deformations. In this work, we use the collective coordinates to describe the magnetic texture and the spin wave packet simultaneously. Based on this new approach, we identify two basic scattering patterns of spin wave across the magnetic texture: the magnonic skew scattering and the side jump, which are quite similar to the electron scattering with impurities in metals. As shown in the figure on the right, spin wave packet expriences the skew scattering as scattered by a magnetic skyrmion - a topologically non-trivial magnetic texture, while the side jump as scattered by a magnetic bubble - a topologically trivial texture. This extension of skew scattering and side jump concepts from electronic to magnetic systems allow us to obtain intuitive understandings on magnetic phenomena.
This work was carried out in collaboration with our former group memeber — Prof. Jin Lan from Tianjin University. For more information, please check this paper published recently in Physical Review B.
[1] J. Lan and J. Xiao, Skew Scattering and Side Jump of Spin Wave across Magnetic Texture, Phys. Rev. B 103, 054428 (2021).