  We experimentally demonstrate the operation of a spin-wave Rowland
spectrometer. In the proposed device geometry, spin waves are coherently
excited on a diffraction grating and form an interference pattern that
spatially separates spectral components of the incoming signal. The diffraction
grating was created by focused-ion-beam irradiation, which was found to locally
eliminate the ferrimagnetic properties of YIG, without removing the material.
We found that in our experiments spin waves were created by an indirect
mechanism, by exploiting nonlinear resonance between the grating and the
coplanar waveguide. Our work paves the way for complex spin-wave optic devices
-- chips that replicate the functionality of integrated optical devices on a
chip-scale.
