Last modified: 2018-07-22
Abstract
Due to their high absorption coefficients (105 cm-1) in the visible range and their appropriate gap, the chalcopyrite semiconductor compounds of I-III-VI2 and II-VI-V2 families are promising candidates for photovoltaic's applications [1]. Also, thanks to the anisotropic characteristic of their linear optical properties (E // oz, E⊥oz), which confers on chalcopyrite materials a large amount of Optical Parametric Oscilator (OPO) and Second Harmonic Generation (SHG) [2] , which gives great performance for lasers based on chalcopyrite compounds [3].
Among IIIIVI2 chalcogenides, CuInSe2 are extensively investigated [4]. Due to the very high cost and environmental concern of III-In system in addition to the high partial pressure of chalcogene VI-Se, the compound CuGaTe2 stands as a potential candidate to be investigated in view of its application for functional materials.
In order to demonstrate the potential of the proposed CuGaTe2 compound for photovoltaic conversion, in WIEN2K code, within the framework of Density functional Theory (DFT) [5], using FP-LAPW approximation [6] and mBj [7] functional for exchange correlation energy, the optoelectronic properties, such as band gap (Eg), absorption coeificient (α(ω)) and photoconductivity ((σ(ω)) in the visible range have been reported, discussed and compared to the available literature data. To the best of our knowledge, for the first time using DFT method the degree of birefringence Δn(ω), which is a predetermining factor for laser performances [8] have been calculated using the relation Δn = ne - no, where ne and no is the extraordinary (n(ω)//oz) and ordinary (n(ω)//oz) refraction indices.
References
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