DFT Analysis of Si- Based Oxide Perovskite for Optoelectronic Applications

Abstract

In the past decade, silicates have garnered significant attention in the geophysical community due to their abundance. However, maintaining cubic silicate perovskites under normal conditions presents challenges, leading to extensive experimental and theoretical investigations to adjust crystal parameters. This study uses density functional theory to investigate the physical characteristics of MSiO₃ (M = Be, Pd) silicate perovskites. The BeSiO₃ and PdSiO₃ compounds were optimized using the Birch–Murnaghan equation to assess their structural stability through pressure–volume data fitting, while elastic constants are determined using the IRelast program to confirm their flexible stability and elastic behavior. The formation energies (Eform) of BeSiO₃ (-3.0845 eV/atom) and PdSiO₃ (-2.2015 eV/atom) confirm their thermodynamic stability, with BeSiO₃ being more stable and energetically favored. BeSiO₃ is a non-magnetic semiconductor with a 2.71 eV bandgap in both spin channels, indicating no spin polarization. PdSiO₃ exhibits half-metallicity, with a 5.04 eV bandgap in the spin-up channel and metallic behavior in the spin-down channel, highlighting its potential for spintronic applications. Optical characteristics, including dielectric functions, extinction coefficients, reflectivity, refractive indices, absorption coefficients, and energy loss factors, are examined closely. The focus is on the sensitivity of both materials to ultraviolet (UV) light, investigating their reactions specifically to this segment of the electromagnetic spectrum. Transparency and maximum reflectivity at specific energies, along with confirmation using Penn's model, suggest potential practical applications of these compounds in optoelectronic devices.