Infrared Faraday effect in ferrite-spinel CoFe$_{2}$O$_{4}$

The spectral, temperature and field dependences of the Faraday effect for single crystals of ferrimagnetic spinel CoFe$_{2}$O$_{4}$ are studied in the infrared range. It is shown that the magneto-optical $q$-factor of CoFe$_{2}$O$_{4}$ varies from -600/dB до +200/dB in the spectral range from 1.5 $\mu$m to 10 $\mu$m and weakly depends on temperature from 200 K to 300 K. The physical mechanisms responsible for the observed Faraday effect are proposed.