Optical properties of ZnTe doped with transition metals (Ti, Cr and Mn)
The electronic and optical properties of \(\text{ Zn }_{1-\mathrm{x}}\text{ M }_\mathrm{x}\text{ Te }\) with (M = Cr, Mn, Ti) have been investigated, within generalized gradient approximation (GGA) using the full potential linear augmented plane wave (FP-LAPW) method as implemented in the WIEN2K code. This work presents detailed information about optical properties like absorbance, refractive index and reflectivity. The result of this study shows that doped ZnTe material with Ti, Cr and Mn shift the absorption spectrum and reflection to the infrared spectral domain or to the ultra violet region, depending on the nature of the dopant. Dielectric functions for different compositional alloys are calculated for 16-atom cubic supercell structure. The calculated band gaps are fitted with a linear equation: (\(\upalpha \text{ h }\upnu )^{2} = \text{ A }(\text{ h }\upnu -\text{ Eg }\)). For all types of doping the position of critical points (CPs) \(\text{ E }_{0}, \text{ E }_{1}\) and \(\text{ E }_{2}\) show good agreement with the experimental data.
optical properties znte fp-lapw dielectric function critical point intraband transition