Role of interface in ferromagnetism of (Zn,Co)O films

TL;DR

This study shows that room temperature ferromagnetism in ZnCoO films is caused by cobalt metal accumulation at the interface, emphasizing the importance of interface effects in magnetic properties.

Contribution

It reveals the critical role of interface cobalt accumulation in inducing ferromagnetism in ZnCoO films grown by ALD, providing new insights into the origin of magnetic behavior.

Findings

RT ferromagnetism due to Co metal at interface

Rejection of alternative explanations for ferromagnetism

Interface effects are key to magnetic properties

Abstract

We demonstrate that room temperature ferromagnetic response (RT FR) of ZnCoO films grown at low temperature by the Atomic layer Deposition (ALD) method is due to Co metal accumulations at the ZnCoO/substrate interface region. The accumulated experimental evi evidences allow us to reject several other explanations of this effect in our samples, despite the fact that some of them are likely to be responsible for the low temperature FM in this class of the material.