Document Type
Article
Original Publication Date
2005
Journal/Book/Conference Title
Applied Physics Letters
Volume
87
Issue
16
DOI of Original Publication
10.1063/1.2106023
Date of Submission
April 2015
Abstract
Contrary to theoretical prediction that Cr-doped bulk ZnO is ferromagnetic, recent experiments on Cr-doped ZnOthin film reveal the coupling to be antiferromagnetic. Using first-principles calculations based on gradient corrected density functional theory, we show that a possible origin of this disagreement may be associated with the site preference of Cr. In bulk, when Cr substitutes Zn,bond contraction occurs and Cr atoms prefer to cluster around O atoms. The ferromagnetic coupling among Cr atoms is driven by Cr 3d and O 2p exchange interactions as in Cr2O cluster. However, when Cr atoms replace Zn on the surface, due to the different bonding environment, bonds expand preventing Cr atoms from clustering around O atoms. Consequently, the coupling between Cr atoms becomes antiferromagnetic.
Rights
Wang, Q., Sun, Q., Jena, P., et al. Magnetic coupling between Cr atoms doped at bulk and surface sites of ZnO. Applied Physics Letters, 87, 162509 (2005). Copyright © 2005 AIP Publishing LLC.
Is Part Of
VCU Physics Publications
Comments
Originally published at http://dx.doi.org/10.1063/1.2106023