An analytical expression for the amplitudes of magnetostatic surface spin waves (MSSWs) propagating in opposite directions at a magnetic film surface is presented. This shows that for a given magnetic field H, it is forbidden for an independent MSSW to propagate along the direction of -H X n, where n is the surface normal. This unidirectional propagation property is confirmed by experiments with both permalloy and iron garnet films of different film thicknesses, and has implications in the design of spin-wave devices such as isolators and spin-wave diodes.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)