Reflection and refraction of spin waves in uniaxial magnets in the geometrical-optics approximation

The laws governing the propagation of magnetization waves are investigated in the geometricaloptics approximation, in which a spin wave can be treated as a ray. The refractive index for a spin wave on the interface between two magnets with different exchange coupling constants and magnetic anisotropy constants is determined. The dependences of the intensity of the reflected wave and the refractive index on the spin-wave frequency and the strength of the external uniform magnetic field are calculated. Estimates of the dimensions of inhomogeneous inclusions that perform functions analogous to the functions of lenses and mirrors in optics are presented. The possibility of using the same inhomogeneities both as lenses and as mirrors, depending on the magnetic field strength, is pointed out. Zh. Tekh. Fiz. 68, 60–63 (February 1998)