Experimental inspection of a computationally-designed NiCrMnSi Heusler alloy with high Curie temperature

Abstract

Nowadays advanced magnetic tunnel junction applications demand very high tunnel magnetoresistance at room temperature, thus it is quite important to explore high Curie temperature Tc half-metallic Heusler alloys. In this article first-principles calculation unveiled that NiCrMnSi has a Tc of 1200 K comparable to that of traditional Co2MnSi Heusler alloys, even though it does not contain a Co element. In addition, we examined whether NiCrMnSi Heusler phase films can be obtained by magnetron sputtering on MgO substrates. The results of the structural analysis and first-principles calculations indicated that the NiCrMnSi Heusler phase is metastable. A possible route to obtain a metastable NiCrMnSi Heusler alloy is to utilize appropriate templates.