High-pressure induced magnetic phase transition in half-metallic KBeO3 perovskite

Abstract

In this paper, we present the study of the structural, mechanical, magneto-electronic and thermodynamic properties of the perovskite KBeO 3. The calculations were performed by the full potential augmented plane wave method, implemented in the WIEN2k code which is based on density functional theory, using generalized gradient approximation. The computed formation energy and elastic constants indicate the synthesizability and mechanical stability of KBeO 3. Moreover, our results showed that the latter is a half-metallic material with halfmetallic gap of 0.67 eV and an integer magnetic moment of 3µ B per unit cell. In addition, KBeO 3 maintains the half-metallic character under the pressure up to about 97 GPa corresponding to the predicted magneticphase transition pressure from ferromagnetic to non-magnetic state. The volume ratio V/V 0 , bulk modulus, heat capacity, thermal expansion and the Debye temperature are analyzed using the quasi-harmonic Debye model.

First‐principles studies on physical properties for new half‐metallic perovskites AFeO3 (A = Ca, Sr, Ba): Spintronics and energy harvesting applications

“…The bulk modulus was found to be amplified in the subsequent directive: B (CaFeO 3 ) > B (SrFeO 3 ) > B (BaFeO 3 ). So compressibility of AFeO 3 (A = Ca, Sr, Ba) follows the same trend and is in good agreement with other calculated results previously [42–46]. This decrease in bulk modulus can be attributed to the increase in volume [47].…”

“…Our computed results of lattice constants are in reasonable settlement with previous work however some underestimation has been observed as compared to experimental lattice constant [42][43][44][45][46]. In order to optimize the performance, the Generalized Gradient Approximation (GGA) is engaged along with the PBE exchange-correlation potential term, which effectively considers the influence of both exchange and correlation effects.…”

“…theoretical/exp. 1.79[42], 1.63[43],/1.47[45] Note: All energy values given here are in eV.F I G U R E 3 Calculated spin-polarized band structures at its equilibrium lattice constant: (A) CaFeO 3 , (B) SrFeO 3 , and (C) BaFeO 3 .…”