• Ferromagnetism in Gd-doped ZnO thin films mediated by defects

• Fulltext

https://www.ias.ac.in/article/fulltext/boms/044/0259

• Keywords

Gd-doped ZnO; radio frequency magnetron sputtering; room temperature ferromagnetism; bound magnetic polaron model; oxygen deficiency; defects.

• Abstract

Defects play an inevitable role in controlling the optical and magnetic properties of ZnO. In this study, defects were introduced in gadolinium (Gd)-doped ZnO films by depositing in pure argon atmosphere. The pristine- and Gddoped (0.05, 0.1 and 1 at%) films were deposited on Si(111) substrate by radio frequency magnetron sputtering at a substrate temperature of 450°C under Ar pressure of 0.02 mbar. Structural, morphological, chemical, optical and magnetic properties of the deposited films were studied by X-ray diffraction and Raman spectroscopy, atomic force microscopy, X-ray photoelectron spectroscopy, photoluminescence and vibrating sample magnetometer, respectively. It is confirmed that oxygen-deficient growth condition leads to the formation of oxygen vacancy (V$_O$$^+) and zinc interstitial (Zn_i$$^+$) defects in the films. It is shown that a critical amount of Zn$_i$$^+ and V_O$$^+$ along with the appropriate amount of Gd$^{3+}$ ions are required to induce room temperature ferromagnetism in Gd-doped ZnO thin film deposited on Si(111) substrate. A possible mechanism has been proposed based on bound magnetic polaron model to explain the observed ferromagnetism.

• Author Affiliations

1. Thin Film Laboratory, Department of Physics, National Institute of Technology, Tiruchirappalli 620015, India

• Bulletin of Materials Science

Volume 45, 2022
All articles
Continuous Article Publishing mode

• Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020