First principle electronic, structural, elastic, and optical properties of strontium titanate

TL;DR

This paper presents a comprehensive ab-initio study of cubic SrTiO3, calculating its electronic, structural, elastic, and optical properties using GGA and LCAO methods, with results aligning well with experimental data.

Contribution

It applies the BZW method within GGA-LCAO to accurately compute multiple properties of SrTiO3, demonstrating improved agreement with experiments.

Findings

Calculated indirect band gap of 3.24 eV matches experimental data

Predicted lattice constant of 3.92 Å agrees with measurements

Bulk modulus estimated at 183 GPa

Abstract

We report self-consistent ab-initio electronic, structural, elastic, and optical properties of cubic SrTiO$_{3}$ perovskite. Our non-relativistic calculations employed a generalized gradient approximation (GGA) potential and the linear combination of atomic orbitals (LCAO) formalism. The distinctive feature of our computations stem from solving self-consistently the system of equations describing the GGA, using the Bagayoko-Zhao-Williams (BZW) method. Our results are in agreement with experimental ones where the later are available. In particular, our theoretical, indirect band gap of 3.24 eV, at the experimental lattice constant of 3.91 \AA{}, is in excellent agreement with experiment. Our predicted, equilibrium lattice constant is 3.92 \AA{}, with a corresponding indirect band gap of 3.21 eV and bulk modulus of 183 GPa.