Theory of Mn-doped I-II-V Semiconductors

Abstract

A recently discovered magnetic semiconductor Ba${}_{1-x}$K${}_x$(Zn${}_{1-y}$Mn${}_y$)${}_2$As${}_2$, with its decoupled spin and charge doping, provides a unique opportunity to elucidate the microscopic origin of the magnetic interaction and ordering in dilute magnetic semiconductors (DMS). We show that (i) the conventional density functional theory accurately describes this material, and (ii) the magnetic interaction emerges from the competition of the short-range superexchange and the longer-range spin-spin interaction mediated by the itinerant As holes. The latter can be viewed as a high-doping extrapolation of with the Schrieffer-Wolff $p-d$ interaction representing an effective Hund's rule coupling, $J_H^{\text{eff}}$. The key difference between the classical double exchange and the actual interaction in DMS is that an effective $J_H^{\text{eff}}$, as opposed to the standard Hund's coupling $J_H$, depends on the Mn $d-$band position with respect to the Fermi level, and thus allows tuning of the magnetic interactions. The physical picture revealed for this transparent system may also be applicable to more complicated DMS systems.

10 pages, 6 figures

References in corpus (3)

• Theory of ferromagnetic (III,Mn)V semiconductors
• Controlling Curie temperature in (Ga,Ms)As through location of the Fermi level within the impurity band
• Tailoring ferromagnetic chalcopyrites

Cited by in corpus (6)

• Local atomic and magnetic structure of dilute magnetic semiconductor (Ba,K)(Zn,Mn)${}_2$As${}_2$
• Microscopic mechanism of high-temperature ferromagnetism in Fe, Mn, and Cr-doped InSb, InAs, and GaSb magnetic semiconductors
• Altermagnetism in MnTe: origin, predicted manifestations, and routes to detwinning
• Anisotropic spin distribution and perpendicular magnetic anisotropy in the layered ferromagnetic semiconductor (Ba,K)(Zn,Mn)${}_2$As${}_2$
• New p- and n-type ferromagnetic semiconductors: Cr-doped BaZn2As2
• Magnetic Properties and Electronic Configurations of Mn Ions in the Diluted Magnetic Semiconductor Ba${}_{1-x}$K${}_x$(Zn${}_{1-y}$Mn${}_y$)${}_2$As${}_2$ Studied by X-ray Magnetic Circular Dichroism and Resonant Inelastic X-ray Scattering