Modulation spectroscopy under uniaxial stress

During the past several years the combination of modulation spectroscopy and static uniaxial stress has been developed into a powerful tool for the investigation of the relationship between the optical properties of semiconductors and their electronic energy bands. Studies of the stress-induced splittings and shifts of energy levels and oscillator strengths as well as the dependence of the induced fine structure on polarization direction and strain configuration have produced a wealth of information concerning the intrinsic properties of the undeformed crystal such as symmetries of interband optical transitions, deformation potentials, spin-exchange interaction of excitons, etc. Symmetry assignments are of considerable value for comparison with band structure calculations while the latter parameters are of significance for comparison with theories based on model calculations and systematic trends such as ionicity. This paper will review experiments and theories dealing with the effects of static uniaxial stress on those optical properties of semiconductors related to the intrinsic properties of the material with special emphasis on the modulated optical spectra.