Role of defects and disorder in the half-metallic full-Heusler compounds

TL;DR

This paper reviews how defects and impurities influence the electronic and magnetic properties of full-Heusler alloys, highlighting their potential in spintronics and the importance of defect control.

Contribution

It presents new insights into the effects of doping, antisites, and vacancies on the half-metallic and magnetic properties of Co-based and Mn-based full-Heusler alloys.

Findings

Doping and disorder can induce half-metallic ferrimagnetism.

Cr(Mn) antisites lead to half-metallic ferrimagnetism.

Vacancies affect the electronic structure of Co and Mn full-Heusler alloys.

Abstract

Half-metallic ferromagnets and especially the full-Heusler alloys containing Co are at the center of scientific research due to their potential applications in spintronics. For realistic devices it is important to control accurately the creation of defects in these alloys. We review some of our late results on the role of defects and impurities in these compounds. More precisely we present results for the following cases (i) doping and disorder in Co$_2$Cr(Mn)Al(Si) alloys, (ii) half-metallic ferrimagnetism appeared due to the creation of Cr(Mn) antisites in these alloys, (iii) Co-doping in Mn$_2$VAl(Si) alloys leading to half-metallic antiferromagnetism, and finally (iv) the occurrence of vacancies in the full-Heusler alloys containing Co and Mn. These results are susceptible of encouraging further theoretical and experimental research in the properties of these compounds.