FIRST PRINCIPLE INVESTIGATION OF THE OPTOELECTRONIC PROPERTIES OF CALCIUM TITANATE (CATIO3)

This study presents a comprehensive first-principle investigation into calcium titanate's structural, electronic, and optical properties (CaTiO3), focusing on its potential applications in optoelectronic devices. Using Density Functional Theory (DFT) implemented in the WIEN2K code, the structural stability, lattice parameters, bulk modulus, and related properties of CaTiO3 were determined. The calculated lattice constant and bulk modulus values closely match existing theoretical and experimental data, validating the structural stability of the cubic phase at the ground state. Electronic band structure analysis revealed that CaTiO3 is an indirect band gap semiconductor, with calculated band gaps of 1.969 eV (GGE-PBE) and 2.825 eV (TB-mBJ), aligning well with prior findings. The optical properties, including the dielectric function, absorption coefficient, extinction coefficient, refractive index, reflectivity, and energy loss function, were analyzed over a range of photon energies. These properties highlight CaTiO3's strong absorption and high reflectivity in the UV range, supporting its use in UV optoelectronic applications. The results underscore CaTiO3's promising characteristics for high-energy optical devices, UV photodetectors, and solar cells. This work adds to the understanding of CaTiO3 optoelectronic behavior and provides a basis for further research and potential modifications to enhance its performance for targeted optoelectronic applications.