Thermoelectric, Structural, Optoelectronic and Magnetic properties of double perovskite Sr2CrTaO6: First principle Study

Highlights: • The structural, opto-electronic, magnetic and thermoelectric properties of Sr₂CrTaO₆ are calculated. • The (FPLAPW) method based on the density functional theory within the GGA, GGA + U and MBJ, is used. • The results show a half-metallic ferrimagnetic ground state for Sr₂CrTaO₆. • Optical properties confirm certainly the useful of Sr₂CrTaO₆ for different applications in the ultraviolet spectrum. -- Abstract: Using the full-potential linearized augmented plane wave method (FP-LAPW) based on the density functional theory (DFT) as implemented in the Wien2k package, first principles calculations were performed to investigate structural, electronic, magnetic, optical and for the first time thermoelectric properties of Sr₂CrTaO₆ double perovskite compound. The exchange correlation potential is treated by the generalized gradient approximation (GGA) and GGA + U where U is on-site Coulomb interaction correction. The trans-blaha-modified Becke–Johnson (TB-mBJ-GGA) is also used. Obtained results for the structural, electronic, and magnetic properties are in good agreement with the available experimental data. Structural and electronic properties show that our compound shows half-metallic ferrimagnetic phase ground state. Optical properties such dielectric function, absorption coefficient and reflectivity were computed and confirm that our compound is very suitable for device applications in the major parts of the spectrum (infrared, visible and ultraviolet). The novelty of our work is the study of thermoelectric properties of Sr₂CrTaO₆ double perovskite such as electrical conductivity, Seebeck coefficient and factor of merit.