Unraveling the strain-induced and spin–orbit coupling effect of novel inorganic halide perovskites of Ca3AsI3 using DFT

Recently, inorganic perovskite materials have been attracting increasing attention owing to their exceptional structural, electronic, and optical characteristics in photovoltaic technology. Ca3AsI3 is a semiconductor material that shares similarities with the group of inorganic metal halide perovskites. Ca3AsI3 possesses a perovskite crystal structure that is cubic, which is classified under the space group Pm-3m (no. 221). Our research aims to analyze how the optical and electronic properties of Ca3AsI3 are influenced by spin–orbit coupling (SOC) and strain using the first-principles density-functional theory. The inorganic Ca3AsI3 perovskite has an electronic band structure that possesses a direct bandgap of roughly 1.58 eV at the Γ(gamma)-point. However, when the SOC relativistic effect is introduced, this value decreases to around 1.27 eV. As the…