Magnetooptic Faraday effect in semiconductors

A review is given of the theoretical investigations of the rotation, in a magnetic field, of the plane of polarization of infrared electromagnetic waves traversing nonmagnetic semiconductors with cubic crystal lattices. It is shown that in the range of wavelengths corresponding to the interband or intraband optical absorption the Faraday effect can be used to determine the energy gaps, reduced effective masses, and the spectroscopic bandsplitting factor. At longer wavelengths corresponding to the free-carrier absorption the Faraday effect can yield the average effective mass at the Fermi level and the Fermi energy can be found at low temperatures and in strong magnetic fields. Uniaxial deformation of crystals with many-valley bands makes it possible to use the free-carrier Faraday effect in the determination of the mass averaged out over an energy ellipsoid as well as the transverse component of the effective mass. A review is also given of the experimental results published for germanium, silicon, indium antimonide, gallium arsenide, and lead chalcogenides, which are optically isotropic in the absence of an external magnetic field.