Theoretical analysis of the electronic, optical and thermal properties of lead strontium telluride alloys Pb1−xSrxTe (x = 0.0−1.0). Issue 4 (1st February 2018)

• Record Type: Journal Article
• Authors: Chouit, F.; Sifi, C.; Slimani, M.; Meradji, H.; Ghemid, S.; Khenata, R.; Rai, D. P.; Bin Omran, S.
• Is Part Of: Philosophical magazine. Volume 98:Issue 4(2018)
• Page Start: 295
• Page End: 311
• Publication Date: 2018-02-01
• Subjects: DFT -- alloys -- electronic properties -- optical properties -- thermal properties; Condensed matter -- Periodicals; Physics -- Periodicals; Matière condensée -- Périodiques; Physique -- Périodiques; 530.41
• DOI: 10.1080/14786435.2017.1403055
• Languages: English
• ISSNs: 1478-6435

Abstract

Abstract: We have simulated different physical properties of Pb1− x Sr x Te semiconductors, using the Ab - initio full potential augmented plane wave (FP-LAPW) method. The two commonly used exchange potentials viz., PBE-GGA and WC-GGA are used along with the most recently developed modified Becke and Johnson (mBJ) potential to study the electronic and optical properties. In this study, we have observed an increase in band gap values as well as the lattice parameter with increasing the concentration of Sr atoms in Pb1− x Sr x Te alloys while the bulk modulus and the refractive index have reverse effect. The microscopic origin of the band gap bowing is explained using the approach of Zunger and co-workers. At ambient conditions ( p = 0, T = 0), the calculations indicate that Pb1− x Srx Te is a direct band gap semiconductor R–R with x = 0.125, 0.25, 0.375, 0.5, 0.625, 0.75 and 0.875. The refractive indices are also calculated using the FP-LAPW method and the models of Moss, Ravindra and the Herve–Vandame. The obtained results are in consistent with the previous available data. To study the thermal effects, the temperature effect on the lattice parameters, thermal expansions, heat capacities the quasi-harmonic Debye model is applied. The Debye temperature is determined from the non-equilibrium Gibbs function.