Spin-wave resonance in Ge : Mn thin films with percolation magnetic ordering

The mechanism of excitation and propagation of spin waves in Ge: Mn thin films with different nominal manganese concentrations (2, 4, and 8 at % Mn) with percolation magnetic ordering is explored. Concentration dependencies of Curie temperature $T_C(n)$ and spin wave rigidity $D(n)$ are determined, which enables to find the index of correlation distance. An exotic percolation magnetic state of samples of Ge: Mn thin films is confirmed by rectifying experimental dependences $D(n)$ and $D/T_C(n)$ in coordinates accepted in the percolation theory.