Phys. Rev. B 103, 214407 (2021)
Geometric magnonics with chiral magnetic domain walls
Jin Lan1,2, Weichao Yu3,2, and Jiang Xiao2,4,5,*
1 Center for Joint Quantum Studies and Department of Physics, School of Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
2 Department of Physics and State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
3 Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
4 Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
5 Shanghai Research Center for Quantum Sciences, Shanghai 201315, China
* xiaojiang@fudan.edu.cn
ABSTRACT
Spin wave, the collective excitation of magnetic order, is one of the fundamental angular momentum carriers in magnetic systems. Understanding the spin wave propagation in magnetic textures lies in the heart of developing pure magnetic information processing schemes. Here we show that the spin wave propagation across a chiral domain wall follows simple geometric trajectories, similar to the geometric optics. And the geometric behaviors are qualitatively different in normally magnetized film and tangentially magnetized film. We identify the lateral shift, refraction, and total reflection of spin wave across a ferromagnetic domain wall. Moreover, these geometric scattering phenomena become polarization dependent in antiferromagnets, indicating the emergence of spin wave birefringence inside antiferromagnetic domain walls.
