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Title: Ferromagnetism induced by planar nanoscale CuO inclusions in Cu-doped ZnO thin films

Abstract

We report ferromagnetism above 300 K in ZnO:xCu (x in at. %) sputtered thin films. For x<1, a large magnetic moment of 1.6 {mu}{sub B}/Cu was observed, which decreases monotonically with increasing x. We find evidence that the ferromagnetic moment is due to Cu-O planar nanophase inclusions in ZnO basal planes. The presence of CuO nanophase is confirmed by transmission electron microscopy, x-ray diffraction, and Raman spectroscopy studies. These inclusions are present even for x<3, where Cu-O structures of a few nanometers in size are observed. Field-cooled and zero-field-cooled magnetization measurements show a bifurcation for temperatures below 300 K.

Authors:
; ;  [1];  [2];  [3]
  1. Department of Physics and Astronomy, Wayne State University, Detroit, Michigan 48201 (United States)
  2. Department of Electrical and Computer Engineering, Wayne State University, Detroit, Michigan 48202 (United States)
  3. Department of Natural Sciences, University of Michigan-Dearborn, Dearborn, Michigan 48128 (United States)
Publication Date:
OSTI Identifier:
20976675
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevB.75.054423; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; COPPER; COPPER OXIDES; DOPED MATERIALS; FERROMAGNETIC MATERIALS; FERROMAGNETISM; INCLUSIONS; MAGNETIC MOMENTS; MAGNETIZATION; NANOSTRUCTURES; RAMAN SPECTRA; RAMAN SPECTROSCOPY; SEMICONDUCTOR MATERIALS; SURFACE COATING; TELLURIUM COMPOUNDS; TEMPERATURE DEPENDENCE; THIN FILMS; TRANSMISSION ELECTRON MICROSCOPY; X-RAY DIFFRACTION; ZINC OXIDES

Citation Formats

Sudakar, C., Lawes, G., Naik, R., Thakur, J. S., and Naik, V. M. Ferromagnetism induced by planar nanoscale CuO inclusions in Cu-doped ZnO thin films. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.054423.
Sudakar, C., Lawes, G., Naik, R., Thakur, J. S., & Naik, V. M. Ferromagnetism induced by planar nanoscale CuO inclusions in Cu-doped ZnO thin films. United States. doi:10.1103/PHYSREVB.75.054423.
Sudakar, C., Lawes, G., Naik, R., Thakur, J. S., and Naik, V. M. Thu . "Ferromagnetism induced by planar nanoscale CuO inclusions in Cu-doped ZnO thin films". United States. doi:10.1103/PHYSREVB.75.054423.
@article{osti_20976675,
title = {Ferromagnetism induced by planar nanoscale CuO inclusions in Cu-doped ZnO thin films},
author = {Sudakar, C. and Lawes, G. and Naik, R. and Thakur, J. S. and Naik, V. M.},
abstractNote = {We report ferromagnetism above 300 K in ZnO:xCu (x in at. %) sputtered thin films. For x<1, a large magnetic moment of 1.6 {mu}{sub B}/Cu was observed, which decreases monotonically with increasing x. We find evidence that the ferromagnetic moment is due to Cu-O planar nanophase inclusions in ZnO basal planes. The presence of CuO nanophase is confirmed by transmission electron microscopy, x-ray diffraction, and Raman spectroscopy studies. These inclusions are present even for x<3, where Cu-O structures of a few nanometers in size are observed. Field-cooled and zero-field-cooled magnetization measurements show a bifurcation for temperatures below 300 K.},
doi = {10.1103/PHYSREVB.75.054423},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 5,
volume = 75,
place = {United States},
year = {Thu Feb 01 00:00:00 EST 2007},
month = {Thu Feb 01 00:00:00 EST 2007}
}
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