Half-metallic ferromagnetism in $\rm{Ti_{2}IrZ (Z = B, Al, Ga, and In)}$ Heusler alloys: A density functional study

Pramana: Journal of physics

K H SADEGHI^1¹ 

[1] Department of Physics, Shahreza Branch, Islamic Azad University, Shahreza, Iran^1

关键词: Half-metals;    Heusler alloys;    $\it{ab-initio}$ calculations;    electronic structure;    magnetic properties;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

The first-principle density functional theory (DFT) calculations were employed to investigate the electronic structures, magnetic properties and half-metallicity of $\rm{Ti_{2}IrZ (Z = B, Al, Ga, and In)}$ Heusler alloys with $\rm{AlCu_{2}Mn-}$ and $\rm{CuHg_{2}Ti-}$type structures within local density approximation and generalised gradient approximation for the exchange correlation potential. It was found that $\rm{CuHg_{2}Ti-}$type structure in ferromagnetic state was energetically more favourable than $\rm{AlCu_{2}Mn-}$type structure in all compounds except $\rm{Ti_{2}IrB}$ which was stable in $\rm{AlCu_{2}Mn-}$type structure in non-magnetic state. $\rm{Ti_{2}IrZ (Z = B, Al, Ga, and In)}$ alloys in $\rm{CuHg_{2}Ti-}$type structure were half-metallic ferromagnets at their equilibrium lattice constants. Half-metallic band gaps were respectively equal to 0.87, 0.79, 0.75, and 0.73 eV for $\rm{Ti_{2}IrB}$, $\rm{Ti_{2}IrAl}$, $\rm{Ti_{2}IrGa}$, and $\rm{Ti_{2}IrIn}$. The origin of half-metallicity was discussed for $\rm{Ti_{2}IrGa}$ using the energy band structure. The total magnetic moments of $\rm{Ti_{2}IrZ (Z = B, Al, Ga, and In)}$ compounds in $\rm{CuHg_{2}Ti}$-type structure were obtained as $2\mu_{B}$ per formula unit, which were in agreement with Slater–Pauling rule $(M_{tot} = Z_{tot}−18)$. All the four compounds were half-metals in a wide range of lattice constants indicating that they may be suitable and promising materials for future spintronic applications.

【 授权许可】

CC BY