Spin current for tuning the band gaps of spin waves

• Published in: Journal of magnetism and magnetic materials Vol. 588; p. 171418
• Main Authors: Morozova, M.A., Lobanov, N.D., Matveev, O.V., Nikitov, S.A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.12.2023
• Subjects: Band gap; Magnonic crystal; Spin current; Spin wave; Magnonic crystal; Band gap; Spin current; Spin wave
• ISSN: 0304-8853
• DOI: 10.1016/j.jmmm.2023.171418

The paper reveals the mechanisms of interaction between the spin current in a conductor with strong spin–orbit coupling (Pt) and the spin wave in ferromagnetic media (YIG) with periodic thickness modulation under conditions of Bragg resonances and interlayer coupling. It is shown that in the structure the conditions for the formation of four Bragg resonances in the first Brillouin zone are satisfied. The effect of the spin current on spin waves with frequencies lying in the band gap region is much greater than the effect on spin waves at frequencies lying outside the band gaps. In particular, the spin current makes it possible to implement the frequency tuning of band gaps, changing the width and depth, as well as the number of band gaps. Moreover, the effect of the spin current on each of the band gaps is different. This feature allows us to talk about the frequency-selective control of band gaps in the spectrum of spin waves using the spin current. •The structure consisting of magnon crystals separated by a film of conducting metal with strong spin–orbit coupling is considered.•The influence of spin current due to spin Hall effect (SHE) on the band gaps is investigated in the structure.•Changing the geometrical parameters of the structure in combination with changing the spin current gives the possibility of frequency-selective control of band gaps in the spin wave spectrum.