- Letter
Magnonic skin effect and magnon valve effect in an antiferromagnetically coupled heterojunction
Phys. Rev. B 104, L020413 – Published 30 July, 2021Erratum Phys. Rev. B 104, 179901 (2021)
DOI: https://doi.org/10.1103/PhysRevB.104.L020413
Abstract
We theoretically study the scattering behavior of spin waves (SWs) at the interface of an antiferromagnetically coupled (AFMC) heterojunction. It is shown that the SWs passing through the interface are evanescent and the incident waves are all reflected back, demonstrating a magnetization-dependent magnon blocking effect in this structure. We also analytically derive the expressions for the decay length of the evanescent waves (EWs). The theoretical result indicates that with the increase of the spin-wave (SW) frequency, the decay length decreases and the EWs are more concentrated at the interface, showing a magnonic skin effect (MSE) which is similar to the skin effect of electromagnetic waves. Furthermore, a positive magnonic Goos-Hänchen shift (MGHS) of the reflected waves is also predicted. It can be understood by an effective reflection interface shift induced by the nonzero decay length of the EWs. The results of micromagnetic simulations are consistent well with all the theoretical findings. Based on the above findings, we also propose a magnon valve without spacers, which shows 100% on-off ratio for magnons. Our work provides insights into SW transmissions in the system of AFMC heterostructures and will serve as a promising tool for future magnonic devices.
