Equiatomic quaternary Heusler alloys: A material perspective for spintronic applications

Abstract

Half-metallic ferromagnetic (HMF) materials show high spin polarization and are therefore interesting to researchers due to their possible applications in spintronic devices. In these materials, while one spin sub band has a finite density of states at the Fermi level, the other sub band has a gap. Because of their high Curie temperature (TC) and tunable electronic been reported in a few systems, which are also discussed in this review. Thus, this review presents a consolidated picture of the magnetic and spintronic properties of this important, but relatively new class of Heusler alloys. It is expected that this will stimulate further interest in these alloys, thereby paving the way for the identification of more HMF and SGS materials. As a result of this, it is expected that more efficient spintronic devices using these alloys would emerge in the near future.

Experimental and theoretical investigation on the possible half-metallic behaviour of equiatomic quaternary Heusler alloys: CoRuMnGe and CoRuVZ (Z = Al, Ga)

“…Many of them are reported to show half-metallic behavior and thus have high spin polarization. [1] In half-metallic materials, one of the spin bands exhibits metallic character whereas, the other spin band exhibits a gap at the Fermi level. Magnetic materials with high spin polarization and high Curie temperature are desirable to improve the performance of spintronic devices such as magnetic tunnel junctions, [2,3] spin injectors, spin transistors, [4,5] and spin valves.…”

Possible spin gapless semiconductor type behaviour in CoFeMnSi epitaxial thin films

“…), Co-doped PbPdO 2 , 3 strained zigzag silicene nanoribbons, 8 and strained Ti 2 C monolayers. 9 Recently, a few equiatomic quaternary Heusler alloys (EQHAs), 10,11 XX 0 YZ (where X, X 0 , and Y are transition metals and Z is a main group element with 1:1:1:1 stoichiometry), which show SGS behaviour, have attracted much interest due to their exceptional magnetic and transport properties over half-metallic ferromagnets (HMFs). EQHAs crystallize in the Y-type or LiMgPdSn prototype structure with space group F 43m (#216).…”

Magnetic tunnel junctions with a B2 -ordered CoFeCrAl equiatomic Heusler alloy

“…The magnetic moments given by summing both spin and orbital components of each element are estimated to be 1. 14 Fig. 1(d)], (iv) the full random swapping of Co and Fe as well as that of Cr and Al [B2, Fig.…”