MAGNETOOPTICAL EFFECTS IN FERROELECTRIC MATERIALS

An expression for high-frequency susceptibility of a ferroelectric mat erial in a constant magnetic field H-0 parallel to the direction of sp ontaneous polarization P-0 has been derived. The reflection and transm ission of light through the ferroelectric is considered for the normal incidence at the surface (along the normal (v) over right arrow to th e surface). It is shown that the polarization plane in reflected light should be rotated through an angle proportional to the product P0H0. For H-0 perpendicular to<(nu)over right arrow>, the angle of rotation of the polarization plane of transmitted light is a periodic function of the optical path, its amplitude being proportional to P0H0. In the H-0 parallel to<(nu)over right arrow> geometry, a weak gyration effect proportional to P0H0 is observed in transmitted light, in addition to the Faraday effect. This effect does not depend on the optical path, and is canceled during backward transmission, in contrast with the Far aday effect. The effect is apparently similar to ''magnetopolarization gyration,'' but the estimates give a much smaller magnitude of the ef fect. The above magnetooptical effects can be observed not only in fer roelectric crystals of any symmetry, but also in insulators in constan t electric and magnetic fields. (C) 1997 American Institute of Physics .