Evidence for Carrier-Induced High-Tc Ferromagnetism in Mn-doped GaN film

TL;DR

This study demonstrates that Mn-doped GaN films exhibit ferromagnetism above room temperature, with the magnetic properties closely linked to carrier transport, suggesting carrier-induced high-Tc ferromagnetism.

Contribution

It provides experimental evidence for carrier-induced high-temperature ferromagnetism in Mn-doped GaN films grown by molecular-beam epitaxy.

Findings

Ferromagnetism persists above room temperature.

High-temperature ferromagnetism is suppressed below 10 K.

Electrical resistivity increases as temperature decreases.

Abstract

A GaN film doped with 8.2 % Mn was grown by the molecular-beam-epitaxy technique. Magnetization measurements show that this highly Mn-doped GaN film exhibits ferromagnetism above room temperature. It is also revealed that the high-temperature ferromagnetic state is significantly suppressed below 10 K, accompanied by an increase of the electrical resistivity with decreasing temperature. This observation clearly demonstrates a close relation between the ferromagnetism with extremely high-Tc and the carrier transport in the Mn-doped GaN film.