Light induced effects in semiconducting ferromagnetics

Summary form only given. Ferromagnetics with semiconducting properties are attractive for magnetoelectronic and optoelectronic applications. We studied materials with a strong mutual influence of electron and magnetic subsystems in order to clear a mechanism of influence of light on magnetic, optical and mechanical characteristics of such systems. The systems in which sensitivity to illumination, in particular by polarized light was observed, were as the following: i) Bi-YIG:Lu,Ga on GGG or semiconducting substrate; ii) doped with Sr manganites - La/sub 0.7/Sr/sub 0.3/MnO/sub 3/, with the peak of magnetoresistivity at room temperature; iii) diluted semiconductors - Co granulars in Si matrix Co/CoSi/sub 2/. Such systems can exhibit a dependence of some magnetic, optical and mechanical parameters on magnetic and electric fields as well as on illumination by light due to induced redistribution of the charge carriers. This problem is of the fundamental interest, e.g. due to attempts to clear the mechanism of spin-dependent transport in FM-SC structures or the surface role in the origin of colossal magnetoresistance, in particular, a mechanism of AFM-FM phase coexistence, etc.