Ferromagnetism and suppression of metallic clusters in Fe implanted ZnO - a phenomenon related to defects?

TL;DR

This study explores how Fe implantation affects ferromagnetism and metallic cluster formation in ZnO, highlighting the role of defects and the suppression of Fe clusters without clear evidence linking Fe magnetic moments to ferromagnetism.

Contribution

It demonstrates suppression of Fe metallic clusters in ZnO and discusses the role of defects in ferromagnetism, challenging the direct correlation between Fe magnetic moments and ferromagnetic behavior.

Findings

Metallic Fe cluster formation is suppressed in Fe-implanted ZnO.

No evidence found linking Fe magnetic moments to ferromagnetism.

Crystalline quality of ZnO substrates is reduced due to preparation.

Abstract

We investigated ZnO(0001) single crystals annealed in high vacuum with respect to their magnetic properties and cluster formation tendency after implant-doping with Fe. While metallic Fe cluster formation is suppressed, no evidence for the relevance of the Fe magnetic moment for the observed ferromagnetism was found. The latter along with the cluster suppression is discussed with respect to defects in the ZnO host matrix, since the crystalline quality of the substrates was lowered due to the preparation as observed by x-ray diffraction.