Nitrides as spintronic materials

TL;DR

This paper reviews progress and debates in the use of group III nitrides, especially GaN, as spintronic materials, discussing magnetic impurities, interactions, and high-temperature ferromagnetism with experimental insights.

Contribution

It provides a comprehensive overview of the current understanding, contradictions, and experimental findings related to magnetic properties and spin coherence in nitrides for spintronics.

Findings

Magnetic impurities' position in GaN lattice remains debated.

High-temperature ferromagnetism observed in (Ga,Mn)N is discussed.

Experimental studies on spin coherence times in GaN are presented.

Abstract

A report of progress in spintronics-related works involving group III nitrides is given emphasizing contradictory opinions concerning basics characteristics of these materials. The actual position of magnetic impurities in the GaN lattice as well as a possible role of magnetic precipitates is discussed. The question whether the hole introduce by the Mn impurities is localized tightly on the Mn d-levels or rather on the hybridized p-d bonding states is addressed. The nature of spin-spin interactions and magnetic phases, as provided by theoretical and experimental findings, is outlined, and possible origins of the high temperature ferromagnetism observed in (Ga,Mn)N are presented. Experimental studies aiming at evaluating characteristic times of spin coherence and dephasing in GaN are described.