Defect-band mediated ferromagnetism in Gd-doped ZnO thin films
Type
ArticleAuthors
Venkatesh, S.Franklin, J. B.
Ryan, M. P.
Lee, J.-S.
Ohldag, Hendrik
McLachlan, M. A.
Alford, N. M.
Roqan, Iman S.
KAUST Department
Physical Sciences and Engineering (PSE) DivisionDate
2015-01-07Permanent link to this record
http://hdl.handle.net/10754/344119Metadata
Show full item recordAbstract
Gd-doped ZnO thin films prepared by pulsed laser deposition with Gd concentrations varying from 0.02–0.45 atomic percent (at. %) showed deposition oxygen pressure controlled ferromagnetism. Thin films prepared with Gd dopant levels (<Gd 0.112 at. %) at low oxygen deposition pressure (<25 mTorr) were ferromagnetic at room temperature. Negative magnetoresistance, electric transport properties showed that the ferromagnetic exchange is mediated by a spin-split defect band formed due to oxygen deficiency related defect complexes. Mott's theory of variable range of hopping conduction confirms the formation of the impurity/defect band near the Fermi level.Citation
Defect-band mediated ferromagnetism in Gd-doped ZnO thin films 2015, 117 (1):013913 Journal of Applied PhysicsSponsors
The authors acknowledge the financial support from the Academic Excellence Alliance (AEA) Grant from King Abdullah University of Science and Technology (KAUST), Saudi Arabia. We thank Dr. Katharina, Lorenz Instituto Superior Técnico, Universidade de Lisboa, Portugal for fitting the RBS data. Soft X-ray spectroscopic studies were carried out at the SSRL, a Directorate of SLAC and an Office of Science User Facility operated for the U.S. DOE Office of Science by Stanford University. J.S.L. acknowledges partial support by the Department of Energy, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract No. DE-AC02-76SF00515.Publisher
AIP PublishingJournal
Journal of Applied PhysicsISSN
0021-89791089-7550