Spin wave reflection from semi-infinite magnonic crystals with diffuse interfaces

The frequency dependence of the coefficient of spin wave reflection from a semi-infinite magnonic crystal with a periodically modulated value of the uniaxial anisotropy and a finite thickness of interfaces has been investigated, assuming a linear distribution of the anisotropy value in the interfaces. The analysis shows that the performance of magnonic devices employing magnonic crystals as a filtering element can degrade as the thickness of interfaces increases, e.g. due to the process of diffusion between constituent layers of the magnonic crystals.