A new class of half-metallic ferromagnets from first principles

Abstract

Half-metallic ferromagnetism (HMFM) occurs rarely in materials and yet offers great potential for spintronic devices. Recent experiments suggest a class of compounds with the `ThCr${}_2$Si${}_2$' (122) structure -- isostructural and containing elements common with Fe pnictide-based superconductors -- can exhibit HMFM. Here we use $ab$ $initio$ density-functional theory calculations to understand the onset of half-metallicity in this family of materials and explain the appearance of ferromagnetism at a quantum critical point. We also predict new candidate materials with HMFM and high Curie temperatures through A-site alloying.

5 figures plus supplementary info

References in corpus (7)

• Half-Metallic Graphene Nanoribbons
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• High-temperature superconductivity in iron-based materials
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