Optical properties of AgGaTe2 monocrystals

Optical transmission spectra of homogeneous non-doped AgGaTe2 monocrystals, grown by the guided crystallization of a melt with the composition close to the compound stoichiometric composition, are measured within 80-350K temperature range. At 300K hole concentration makes up (1-5x1013cm-3, and their mobility - 5-8 cm2/Bxs. The edge absorption spectrum analysis in the natural radiation shows that AgGaTe2 is a straight-zone semiconductor with forbidden zone width Eg=1.32 eV (300K), in 80-350 K interval Eg dropps according to the linear law with the temperature coefficient dEg/dT≅ 3.6x10-4 eV/K. AgGaTe2 photosensitivity in 0.6-3 eV range is detected. Photosensitive structure are as well produced in the crystals created; including Schottky diodes and electrochemical cells. Investigations into complete and photoactive absorption in linearly polarized light allow one to detect linear dichroism and photopleochroism which correspond to chalkopyrite lattice symmetry. The results obtained point out to the possibilities of AgGaTe2 monocrystal application in polarization photoelectronics