Abstract
The present work includes a first principle study of the electronic structure, elastic, magnetic and thermal properties of Co-based ternary full-Heusler alloys Co2CrX (x=Al,Ga). The lattice constant, bulk modulus, magnetic moment and density of states are studied using the full-potential linearized augmented plane wave method with the Generalized Gradient Approximation (GGA) as functional of exchange and correlation. This shows that the magnetic properties of the compound are dependent on electron concentration of main group element and all concentrations are magnetic in their equilibrium L21 structure. The calculations show that the alloys with all concentration are true half-metallic materials and exhibit 100% spin polarization at the Fermi level where it can be shifted within the energy-gap. In addition, the quasi-harmonic Debye model is applied to determine the thermal properties of the alloy.
Highlights
With the development of spintronic devices in the recent years, materials with complete spin polarization at the Fermi level EF have attracted much attention because they are of great interest for scientific research and industrial applications [1,2,3] .An important class of materials which are at present under intense study are the so-called half-metals [4]
The Heusler ternary alloys are determined by the generic formulas X2YZ or XYZ [8, 9],The -Heusler alloys (X2YZ) where X and Y are transition metals, and Z is an element of group III, IV or V, in some cases, Y is replaced by either a rare earth element
The plane wave cut-off parameter is taken as RMT*Kmax=8.5, The Brillouin zone sampling was performed according to the Monkhorst–Pack scheme and for k-space integration, a (14 * 14 * 14) mesh was used resulting in 104k points of the irreducible part in the Brillouin zone [12].Study of thermodynamic properties was performed within the quasi-harmonic Debye model implemented in the Gibbs program [13]
Summary
With the development of spintronic devices in the recent years, materials with complete spin polarization at the Fermi level EF have attracted much attention because they are of great interest for scientific research and industrial applications [1,2,3] .An important class of materials which are at present under intense study are the so-called half-metals [4]. The X2YZ Heusler compounds crystallize in the cubic L21 (AlCu2Mn-type) structure with the space group Fm-3m In this structure, X, Y and Z atoms are placed on the Wyckoff positions 8c (1/4, 1/4, 1/4), 4a (0, 0, 0) and 4b (1/2, 1/2, 1/2), respectively. This structure is frequently observed when the nuclear charge of the Y element is larger than the one of the X element from the same period, that is Z(Y) > Z(X) for two 3d transition metals In this structure, X atoms occupy the nonequivalent 4a (0, 0, 0) and 4c (1/4, 1/4, 1/4) positions, while Y and Z atoms are located on 4b (1/2, 1/2, 1/2) and 4d (3/4, 3/4, 3/4) Wyckoff positions, respectively [10].The two compounds Co2CrAl and Co2CrGa these are new innovative materials for many application spinotronique, these alloys have a special interest because of their relatively high Curie temperature.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
