First-principles calculations to investigate structural, electronic, and optical properties of zinc-blende CdxMg(1-x)TeyS(1- y) matched to CdX (X= S, Te) for Predicting critical thickness and corrective Term's effect

• Published in: Solid state communications 2023-08, Vol.368, p.115189, Article 115189
• Main Authors: Chahed, Faiza, Djoudi, Lakhdar, Boucharef, Mohamed, Merabet, Mostefa, Benalia, Salah Eddin, Kadjaoud, Mohamed
• Format: Article
• Language: English
• Subjects: DFT; GGA; mBJ; Optical spectra; Optoelectronic properties; Structural properties
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2023.115189

We report in the present paper ab initio calculations of the structural, electronic and optical properties of zinc blende quaternary alloys CdxMg(1-x)TeyS(1-y) lattice matched to CdX (X = S, Te) exploring the density functional method within the generalized gradient approximation (GGA). From the obtained values of the ground state energy, we have determined the structural parameters and the band gap energies. We found an underestimation of the gap energies obtained for both (GGA-PBE) and the Modified Becke-Johnson exchange potential (TB-mbJ) approximations for the CdS, CdTe, MgS, and MgTe. Even though mbJ significantly corrects the energy gaps, it is no longer valid to properly reproduce the exchange-correlation potential. Consequently, we tend to use the corrective term ΔE to exploit it to enhance the electronic band structures. Moreover, we have reported the concentration depending on the refractive index and the dielectric function using (mbJ). The critical thickness, for which the lattice of the CdxMg(1-x)TeyS(1-y) matches CdS and CdTe, respectively, are determined. The results show that for all Cd and Te incorporated amounts, the CdxMg(1-x)TeyS(1-y) lattice matched to CdX (X = S, Te) substrate alloys exhibits a semiconducting behavior with a small lattice mismatching ratio which might make CdxMg(1-x)TeyS(1-y)/CdX materials promising and useful for optoelectronic applications. •Investigate the structural, electronic, and optical properties of CdS, CdTe, MgTe and MgS in zinc-blende structure.•Investigate the structural, electronic and optical properties of CdxMg(1-x)TeyS(1-y) in zincblende structure.•Investigate the optical parameters quantitively.•The direct band-gaps for CdS, CdTe, MgTe and MgS are underestimated relate to the room-temperature experimental gaps.•The obtained wave lengths for CdxMg(1-x)TeyS(1-y) matched to CdX (X = S, Te) are obviously confined between 300 and 500 nm.