Defect-mediated ferromagnetism in insulating Co-doped anatase TiO2 thin films

K. Griffin Roberts, M. Varela, Sergey Rashkeev, S. T. Pantelides, S. J. Pennycook, Kannan M. Krishnan

Research output: Contribution to journalArticle

59 Citations (Scopus)

Abstract

The nature of the defect responsible for room-temperature ferromagnetism in Co-doped anatase TiO2 has remained elusive. Here we report atomic-resolution Z -contrast images of epitaxially grown Co0.03: TiO2 films showing that Co atoms are dispersed and occupy preferred interstitial sites. Density-functional calculations found that these sites are the lowest-energy configuration of Co in anatase and that O vacancies (VO), introduced by annealing, anchor the Co atoms into Co- Ti+3 -VO complexes. The calculated magnetic moment is in agreement with our measured value and the calculated Co x-ray absorption spectrum is in agreement with data published in the literature.

Original languageEnglish
Article number014409
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume78
Issue number1
DOIs
Publication statusPublished - 7 Jul 2008
Externally publishedYes

Fingerprint

Ferromagnetism
anatase
Titanium dioxide
ferromagnetism
Thin films
Atoms
Defects
x ray spectra
defects
image contrast
thin films
Magnetic moments
Anchors
x ray absorption
Vacancies
Density functional theory
atoms
Absorption spectra
interstitials
magnetic moments

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Defect-mediated ferromagnetism in insulating Co-doped anatase TiO2 thin films. / Griffin Roberts, K.; Varela, M.; Rashkeev, Sergey; Pantelides, S. T.; Pennycook, S. J.; Krishnan, Kannan M.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 78, No. 1, 014409, 07.07.2008.

Research output: Contribution to journalArticle

Griffin Roberts, K. ; Varela, M. ; Rashkeev, Sergey ; Pantelides, S. T. ; Pennycook, S. J. ; Krishnan, Kannan M. / Defect-mediated ferromagnetism in insulating Co-doped anatase TiO2 thin films. In: Physical Review B - Condensed Matter and Materials Physics. 2008 ; Vol. 78, No. 1.
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