Magnetotransmission in a magnetostrictive CoFe$_2$O$_4$ crystal in the Faraday geometry

It is shown that the magnetotransmission of unpolarized infrared radiation in the magnetostrictive crystal of CoFe$_2$O$_4$ ferrite spinel in the Faraday geometry can be as high as 30% at a magnetic field of 7.5 kOe. This effect is related to the field-induced shift of the fundamental absorption edge, as well as to changes in the intensity and positions of the impurity absorption bands. Correlation between the magnetic field dependence of magnetotransmission and magnetostriction is revealed. The contribution of the Faraday effect to the magnetotransmission is estimated. The analysis of magneto-optical and magnetoelastic characteristics taking into account the contribution of the deformation potential for the valence band is performed.