Optical and photoelectric properties of anisotropic semiconductors

Members of the group


Spectra of optical absorption, photoconductivity and short-circuit photocurrent are known to be very informative for investigations of the peculiarities of the band structure. However the studies on these spectra for CdAs2 and ZnAs2 anisotropic crystals are very limited.
Using the mentioned methods CdAs2 crystals were studied in a polarized light over the temperature range of 77-300 K, and two indirect and one direct interband optical transitions were observed. The energies of effective phonons, bonding energies of indirect excitons, and the temperature dependence of energy gap were determined.
The investigations of ZnAs2 crystals with very low residual impurity concentration have unambiguously shown that the first absorption edge in ZnAs2 is determined by indirect optical transitions. The excitonic absorption peak associated with direct interband transitions was observed in the 77-300 K temperature range. This observation was possible due to high structural perfection and purity of the studied crystals.

Selected publications:

Physics of Semiconductors division