First Principles Study Of Structural, Electronic and Optical Properties Of Manganese Doped Zinc Telluride: A Density Functional Theory Study.

Abstract

This thesis presents a thorough first-principles investigation into the structural, electronic, and optical properties of manganese-doped zinc telluride (ZnTe:Mn), a semiconductor with significant applications in optoelectronics. The incorporation of manganese into zinc telluride enhances its structural, electronic, and optical characteristics, thereby improving its functionality in spintronic devices. Utilizing density functional theory (DFT) and the open-source plane-wave code Quantum ESPRESSO, this study examines the effects of manganese doping on lattice parameters, bond lengths, and optical responses within the ZnTe crystal structure. The optimal lattice parameter for pure ZnTe is experimentally determined to be 6.10 Å, which increases to 6.24 Å upon manganese doping. The band gap of pure ZnTe is 2.26 eV, decreasing to 1.96 eV with manganese incorporation. Additionally, the refractive index of pure ZnTe, measured at 3, drops to 2.85 with doping. While the real component of the dielectric function for pure ZnTe is found to be 9.3, computational results show a reduction to 8.67 with manganese inclusion. These findings enhance our understanding of manganese-doped zinc telluride and highlight its potential in advanced electronic and optoelectronic devices, particularly in spintronics and photonics. This underscores the critical role of first-principles calculations in predicting and optimizing semiconductor properties for emerging technologies in the electronic and optoelectronic fields.