The focusing properties of spin wave with Fresnel lens phase profile

Abstract

The manipulation of spin waves has been essential for the application of spin waves. In this article, we report a Fresnel lens for focusing the magnetostatic surface spin waves on a ferromagnetic film and verify its propagation characteristics by micromagnetic simulation. By coding the phase profile of Fresnel lens on the excitation source, a clear focusing point of the spin waves is observed according to simulation results. Additionally, the focal length can be tuned effectively with external magnetic fields. This work can extend the application scenario of spin waves.