Defect-band mediated ferromagnetism in Gd-doped ZnO thin films

Handle URI:
http://hdl.handle.net/10754/344119
Title:
Defect-band mediated ferromagnetism in Gd-doped ZnO thin films
Authors:
Venkatesh, S.; Franklin, J. B.; Ryan, M. P.; Lee, J.-S.; Ohldag, Hendrik; McLachlan, M. A.; Alford, N. M.; Roqan, Iman S. ( 0000-0001-7442-4330 )
Abstract:
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.
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Citation:
Defect-band mediated ferromagnetism in Gd-doped ZnO thin films 2015, 117 (1):013913 Journal of Applied Physics
Publisher:
AIP Publishing LLC
Journal:
Journal of Applied Physics
Issue Date:
7-Jan-2015
DOI:
10.1063/1.4905585
Type:
Article
ISSN:
0021-8979; 1089-7550
Sponsors:
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.
Additional Links:
http://scitation.aip.org/content/aip/journal/jap/117/1/10.1063/1.4905585
Appears in Collections:
Articles; Physical Sciences and Engineering (PSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorVenkatesh, S.en
dc.contributor.authorFranklin, J. B.en
dc.contributor.authorRyan, M. P.en
dc.contributor.authorLee, J.-S.en
dc.contributor.authorOhldag, Hendriken
dc.contributor.authorMcLachlan, M. A.en
dc.contributor.authorAlford, N. M.en
dc.contributor.authorRoqan, Iman S.en
dc.date.accessioned2015-02-04T07:27:18Z-
dc.date.available2015-02-04T07:27:18Z-
dc.date.issued2015-01-07en
dc.identifier.citationDefect-band mediated ferromagnetism in Gd-doped ZnO thin films 2015, 117 (1):013913 Journal of Applied Physicsen
dc.identifier.issn0021-8979en
dc.identifier.issn1089-7550en
dc.identifier.doi10.1063/1.4905585en
dc.identifier.urihttp://hdl.handle.net/10754/344119en
dc.description.abstractGd-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.en
dc.description.sponsorshipThe 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.en
dc.language.isoenen
dc.publisherAIP Publishing LLCen
dc.relation.urlhttp://scitation.aip.org/content/aip/journal/jap/117/1/10.1063/1.4905585en
dc.rightsArchived with thanks to Journal of Applied Physics.en
dc.titleDefect-band mediated ferromagnetism in Gd-doped ZnO thin filmsen
dc.typeArticleen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalJournal of Applied Physicsen
dc.eprint.versionPublisher's Version/PDFen
dc.contributor.institutionDepartment of Materials, Imperial College London, London SW7 2AZ, United Kingdomen
dc.contributor.institutionStanford Synchrotron Radiation Light source (SLAC), National Accelerator Laboratory, Menlo Park, California 94025, USAen
dc.contributor.institutionDepartment of Materials, Imperial College London, London SW7 2AZ, United Kingdomen
dc.contributor.affiliationKing Abdullah University of Science and Technology (KAUST)en
kaust.authorRoqan, Iman S.en
kaust.authorVenkatesh, Sureshen
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