Magnetism in Mn delta-doped cubic GaN: density-functional theory studies

TL;DR

This study uses density-functional theory to explore how Mn delta-doping affects magnetism in cubic GaN, revealing stable half-metallic ferromagnetism and antiferromagnetism in different structures, with implications for 2D magnetic materials.

Contribution

It provides a detailed theoretical analysis of magnetic properties in Mn delta-doped cubic GaN, highlighting the stability of ferromagnetic and antiferromagnetic states in various doping configurations.

Findings

Single-layer delta-doping shows half-metallic ferromagnetism.

Double-layer delta-doping exhibits antiferromagnetism with high spin-flip energy.

Delta-doping enhances two-dimensional magnetic behavior.

Abstract

The magnetism in 12.5% and 25% Mn delta-doped cubic GaN has been investigated using the density-functional theory calculations. The results show that the single-layer delta-doping and half-delta-doping structures show robust ground state half-metallic ferromagnetism (HMF), and the double-layer delta-doping structure shows robust ground state antiferromagnetism (AFM) with large spin-flip energy of 479.0 meV per Mn-Mn pair. The delta-doping structures show enhanced two-dimensional magnetism. We discuss the origin of the HMF using a simple crystal field model. Finally, we discuss the antiferromagnet/ferromagnet heterostructure based on Mn doped GaN.