• Zhu, Weijia
• Flajšman, Lukáš
• Qin, Huajun
• Van Dijken, Sebastiaan
• Taniyama, Tomoyasu

Abstract

| openaire: EC/H2020/861145/EU//BeMAGIC Funding Information: This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 861145. The work was supported by the Academy of Finland (Grant Nos. 317918 and 325480), JST CREST under Grant No. JPMJCR18J1, and JSPS KAKENHI under Grant No. 21H04614. Lithography was performed at the OtaNano—Micronova Nanofabrication Centre of Aalto University. Computational resources were provided by the Aalto Science-IT project. Publisher Copyright: © 2022 Author(s). ; We report zero-field routing of spin waves in a multiferroic heterostructure comprising a ferromagnetic Fe film and a ferroelectric BaTiO3 substrate with fully correlated strain-coupled domains. In the Fe film, a regular alternation of magnetic anisotropy produces a back-and-forth rotation of uniform magnetization in zero magnetic field. Spin waves propagating across this domain structure are refracted at the magnetic domain walls because of abrupt changes in the dispersion relation and phase velocity. Using super-Nyquist sampling magneto-optical Kerr effect microscopy, we image the routing of spin waves and analyze the dependence of the effect on frequency and the propagation direction. We find that spin waves are routed efficiently by angles up to 60° without measurable loss in amplitude. The experimental results are reproduced by micromagnetic simulations and calculations based on the modified Snell's law for magnonics. ; Peer reviewed

Topics

• dispersion
• phase
• simulation
• magnetization
• lithography
• magnetic domain wall
• microscopy