Hydrostatic pressure dependent structural, elastic, vibrational, electronic, and optoelectronic properties of superconducting BaCuO3: A DFT insight

Abstract

In the present study, the dependence of structural, elastic, electronic, and optoelectric properties of BaCuO3 on hydrostatic pressure is presented via density functional theory. The mechanical and dynamical stabilities of this compound have been established from elastic constants and phonon spectra, respectively. The different mechanical parameters have been reported and compared with other perovskite materials. Different elastic constants revealed that BaCuO3 is soft material, ductile in nature, and elastically anisotropic. Due to the lower value of Young's modulus, BaCuO3 can be used as thermal barrier coating. The elastic constants, moduli, and Debye-temperature show monotonic variation with pressure. The superconducting transition temperature, Tc = 9.96 K, is estimated from phonon calculations of BaCuO3. The electronic band structure reveals the metallic characteristic where the dominant behavior of Cu-3d and O-2p orbitals at Fermi-level is confirmed from the partial density of states (DOS) calculations. With the applied hydrostatic pressure, strong hybridization between Cu-3d and O-2p orbitals is observed. The peak positions in dielectric constants, absorption and conductivity spectra as well as in reflectivity and loss function are strongly influenced by the external pressure. The reduction of intensity and shifting of the peak position are observed at 18 GPa in different optical parameters which is due to the transition from the initial state 2p63d9 to the final state 2p53d10 of Cu atom. The optical properties reveal that BaCuO3 is photoconductive and suitable for optoelectronic device applications.