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Stoner Ferromagnetism in Hole-Doped CuM^IIIAO₂ with M^IIIA = Al, Ga, and In.

ABSTRACT: Using density functional theory calculations, we examine the effect of hole doping on the magnetic and electronic properties of CuM^IIIAO₂, with M^IIIA = Al, Ga, and In. CuM^IIIAO₂ nonmagnetic semiconductors switch to ferromagnetic half-metals upon hole doping. For CuAlO₂, the nonmagnetic-to-ferromagnetic transition occurs for hole densities of ∼7 × 10¹⁹/cm³. Ferromagnetism arises from an exchange splitting of the electronic states at the valence band edge, and it can be attributed to the high-lying Cu-d states. Hole doping induced by cation vacancies and substitutional divalent dopants is also investigated. Interestingly, both vacancies and nonmagnetic divalent dopants result in the emergence of ferromagnetism.

SUBMITTER: Iordanidou K

PROVIDER: S-EPMC8289245 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Stoner Ferromagnetism in Hole-Doped CuMIIIAO2 with MIIIA = Al, Ga, and In.

Iordanidou Konstantina K Persson Clas C

ACS applied materials & interfaces 20210621 25

Using density functional theory calculations, we examine the effect of hole doping on the magnetic and electronic properties of CuMIIIAO2, with MIIIA = Al, Ga, and In. CuMIIIAO2 nonmagnetic semiconductors switch to ferromagnetic half-metals upon hole doping. For CuAlO2, the nonmagnetic-to-ferromagnetic transition occurs for hole densities of ∼7 × 1019/cm3. Ferromagnetism arises from an exchange splitting of t ...[more]

PMID: 34152119

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