Investigating structural, electronic and optical properties of CdS:Cr (A GGA and GGA+U study)

Abstract

In this research study, we investigate the structural, electronic and optical properties of the Cr doped rocksalt CdS using a full-potential linearized augmented plane wave (FPLAPW) method, within the density functional theory. The calculations are made within the GGA and GGA + U approaches, employed in the Wien2K code. Adding the Hubbard term, gives better description of the system with strong correlation of d-electrons. Results of the partial density of states are discussed in terms of the Cd 4d10 4p6 5s2, Cr 3p6 3 d5 4s1 and S 3s2 3p4. The density of states and band structure shows metallic nature. PDOS plots represent the p-d hybridization and by comparing the distribution of the DOS under GGA and GGA + U, it is evident that local position of states is different with addition of Hubbard term. We calculate the structural properties such as the lattice constants, bulk moduli, and cohesive energies which are consistent with the already reported findings. The cohesive energy suggests that CdS is stable with Cr addition. The optical absorption shows blueshift when GGA is employed but exhibits redshift, upon implication of GGA + U. Results are in good agreement with the literature. Enhanced optoelectronic properties of CdS:Cr provides a road map for its potential uses in the light harvesting field of optoelectronics, displays, spintronics, sensors and energy devices.