A study of the electronic structures and optical properties of CuXTe2 (X = Al, Ga, In) ternary semiconductors

Using first-principle calculations, the electronic and optical properties of chalcopyrite crystals CuXTe2 (X = Al, Ga, In) are analyzed in detail. It is found that the prominent peaks of the dielectric functions and the refractive index significantly shift towards lower energies in the order of Al → Ga → In, and these compounds are characterized by similar optical spectra with some anisotropy effects. Present findings predict that CuGaTe2 and CuInTe2 are promising for photovoltaics due to their high absorption of solar radiations and photoconductivity in the visible range.