Pressure effect on mechanical, magnetic and optoelectronic properties of SrCoO3-Perovskite: FP-(L)APW+lo investigation

Abstract

The present work is a complementary and comparative study to the work already done on elastic, magnetic and optoelectronic behaviors of SrCoO3, from which we have studied the effect of hydrostatic pressure on these behaviors. FP-(L)APW+lo method was used with GGA-PBE and GGA-PBEsol as exchange-correlation functional. The structural results obtained by GGA-PBEsol at zero pressure are in perfect agreement with those found previously in comparison with those obtained by GGA-PBE. The obtained elastic constants under a pressure range between 0 GPa and 10 GPa have been calculated by the theoretical model implemented in IRelast package. Therefore, the generalized stability criteria are all positive under a pressure lower than 10 GPa which allows to say that SrCoO3 maintains its mechanical stability under this pressure range. Several related mechanical quantities have been determined and the obtained results are in agreement with those found previously. The obtained values of Zener's anisotropy factor and the universal elastic anisotropy index as well as the analysis of the directional dependence surface of Young's modulus indicate the large elastic anisotropy of SrCoO3, which decrease with increasing pressure. Despite the metallic behavior of SrCoO3, it is important to take into account the strong correlation between 3d-cobalt electrons from which GGA+U has been used for the study of magnetic and optoelectronic properties of this compound after estimating the effective on-site Coulomb interaction parameter “Ueff” by cLDA method. Despite Hubbard's correction, the electronic band structure has shown that SrCoO3 is a metal, which is in agreement with previous results. The qualitative and quantitative analysis of the bonds between the atoms that form SrCoO3 has shown that the ionic character is predominant. The optical properties under the effect of pressure, which are very important in practical applications, are extensively analyzed and interpreted by the determination of the dielectric function.