Robust Half-Metallicity and Electronic Structure of the New Full-Heusler Compounds CsBaX2 (X = C, N, and O)

Abstract

The electronic structure and magnetism of new Heusler alloys of CsBaX 2 (X = C, N, and O) were investigated within density functional theory (DFT) using the selfconsistent full-potential linearized augmented plane wave (FPLAPW) method. The CsBaC 2 in the AlCu 2 Mn-type was a half-metallic ferromagnet while it was a nonmagnetic metal in CuHg 2 Ti-type structure. CsBaN 2 and CsBaO 2 compounds in both structures were half-metallic ferromagnets. The majority band gap for CsBaC 2 in the AlCu 2 Mntype was obtained equal to 1.67 eV and for CsBaN 2 and CsBaO 2 compounds in the AlCu 2 Mn-type (CuHg 2 Ti-type) structure were calculated equal to 2.34 (2.29) eV and 3.53 (2.76) eV, respectively. The origin of half-metallicity was also studied using the band structure calculations and density of states (DOSs). The total magnetic moments of CsBaC 2 , CsBaN 2 , and CsBaO 2 compounds were, respectively, obtained as 5μ B , 3μ B , and 1μ B per formula unit at the equilibrium lattice parameter, which were in agreement with Slater-Pauling rule (M tot = 12-Z tot ). The CsBaX 2 (X = C, N, and O) compounds kept their half-metallic characteristic in a wide range of lattice constants in comparison with Heusler alloys including transition metals, which makes them promising and attractive materials in spintronic field.

A Monte Carlo study of the yttrium-based Heusler alloys: Y2CrGa and YFeCrGa

“…As far as we know, most research studies have focused on the half-metallic magnetic alloys (Luo et al , 2009, 2010a, b; Feng et al , 2010; Bensaid et al , 2016; Hoshino et al , 2010; Kurfiß and Anton, 2003; Li et al , 2008). In recent years, the half-metallicity was approved in the arrangements of Heusler alloys, except for the transition metals, such as RbSrX 2 (X = C, N and O), KCaX 2 (X = C, N and O), RbSrZ (Z = C, Si and Ge) and CsBaX 2 (X = C, N and O) (Rozale et al , 2013a, b; Bagverdi and Ahmadian, 2015; Erfan and Ahmadian, 2015). The quaternary equiatomic Heusler alloys (EQHAs) are represented as XX'YZ.…”