Negligible magnetism in excellent structural quality CrxTi1-xO2 anatase

Contrast with high-TC ferromagnetism in structurally defective CrxTi1-xO2

T. C. Kaspar, S. M. Heald, C. M. Wang, J. D. Bryan, T. Droubay, V. Shutthanandan, S. Thevuthasan, D. E. McCready, A. J. Kellock, D. R. Gamelin, S. A. Chambers

Research output: Contribution to journalArticle

158 Citations (Scopus)

Abstract

We reexamine the mechanism of ferromagnetism in doped TiO2 anatase, using epitaxial Cr: TiO2 with excellent structural quality as a model system. In contrast to highly oriented but defective Cr: TiO2 (∼0.5μB/Cr), these structurally superior single crystal films exhibit negligible ferromagnetism. Similar results were obtained for Co: TiO2. We show for the first time that charge-compensating oxygen vacancies alone, as predicted by F-center mediated exchange, are not sufficient to activate ferromagnetism. Instead, the onset of ferromagnetism correlates with the presence of structural defects.

Original languageEnglish
Article number217203
JournalPhysical Review Letters
Volume95
Issue number21
DOIs
Publication statusPublished - 18 Nov 2005
Externally publishedYes

Fingerprint

anatase
ferromagnetism
Oxygen
color centers
titanium dioxide
single crystals
defects
oxygen

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Negligible magnetism in excellent structural quality CrxTi1-xO2 anatase : Contrast with high-TC ferromagnetism in structurally defective CrxTi1-xO2. / Kaspar, T. C.; Heald, S. M.; Wang, C. M.; Bryan, J. D.; Droubay, T.; Shutthanandan, V.; Thevuthasan, S.; McCready, D. E.; Kellock, A. J.; Gamelin, D. R.; Chambers, S. A.

In: Physical Review Letters, Vol. 95, No. 21, 217203, 18.11.2005.

Research output: Contribution to journalArticle

Kaspar, TC, Heald, SM, Wang, CM, Bryan, JD, Droubay, T, Shutthanandan, V, Thevuthasan, S, McCready, DE, Kellock, AJ, Gamelin, DR & Chambers, SA 2005, 'Negligible magnetism in excellent structural quality CrxTi1-xO2 anatase: Contrast with high-TC ferromagnetism in structurally defective CrxTi1-xO2', Physical Review Letters, vol. 95, no. 21, 217203. https://doi.org/10.1103/PhysRevLett.95.217203
Kaspar, T. C. ; Heald, S. M. ; Wang, C. M. ; Bryan, J. D. ; Droubay, T. ; Shutthanandan, V. ; Thevuthasan, S. ; McCready, D. E. ; Kellock, A. J. ; Gamelin, D. R. ; Chambers, S. A. / Negligible magnetism in excellent structural quality CrxTi1-xO2 anatase : Contrast with high-TC ferromagnetism in structurally defective CrxTi1-xO2. In: Physical Review Letters. 2005 ; Vol. 95, No. 21.
@article{706ffd50a02b4d7f9e49769698887627,
title = "Negligible magnetism in excellent structural quality CrxTi1-xO2 anatase: Contrast with high-TC ferromagnetism in structurally defective CrxTi1-xO2",
abstract = "We reexamine the mechanism of ferromagnetism in doped TiO2 anatase, using epitaxial Cr: TiO2 with excellent structural quality as a model system. In contrast to highly oriented but defective Cr: TiO2 (∼0.5μB/Cr), these structurally superior single crystal films exhibit negligible ferromagnetism. Similar results were obtained for Co: TiO2. We show for the first time that charge-compensating oxygen vacancies alone, as predicted by F-center mediated exchange, are not sufficient to activate ferromagnetism. Instead, the onset of ferromagnetism correlates with the presence of structural defects.",
author = "Kaspar, {T. C.} and Heald, {S. M.} and Wang, {C. M.} and Bryan, {J. D.} and T. Droubay and V. Shutthanandan and S. Thevuthasan and McCready, {D. E.} and Kellock, {A. J.} and Gamelin, {D. R.} and Chambers, {S. A.}",
year = "2005",
month = "11",
day = "18",
doi = "10.1103/PhysRevLett.95.217203",
language = "English",
volume = "95",
journal = "Physical Review Letters",
issn = "0031-9007",
publisher = "American Physical Society",
number = "21",

}

TY - JOUR

T1 - Negligible magnetism in excellent structural quality CrxTi1-xO2 anatase

T2 - Contrast with high-TC ferromagnetism in structurally defective CrxTi1-xO2

AU - Kaspar, T. C.

AU - Heald, S. M.

AU - Wang, C. M.

AU - Bryan, J. D.

AU - Droubay, T.

AU - Shutthanandan, V.

AU - Thevuthasan, S.

AU - McCready, D. E.

AU - Kellock, A. J.

AU - Gamelin, D. R.

AU - Chambers, S. A.

PY - 2005/11/18

Y1 - 2005/11/18

N2 - We reexamine the mechanism of ferromagnetism in doped TiO2 anatase, using epitaxial Cr: TiO2 with excellent structural quality as a model system. In contrast to highly oriented but defective Cr: TiO2 (∼0.5μB/Cr), these structurally superior single crystal films exhibit negligible ferromagnetism. Similar results were obtained for Co: TiO2. We show for the first time that charge-compensating oxygen vacancies alone, as predicted by F-center mediated exchange, are not sufficient to activate ferromagnetism. Instead, the onset of ferromagnetism correlates with the presence of structural defects.

AB - We reexamine the mechanism of ferromagnetism in doped TiO2 anatase, using epitaxial Cr: TiO2 with excellent structural quality as a model system. In contrast to highly oriented but defective Cr: TiO2 (∼0.5μB/Cr), these structurally superior single crystal films exhibit negligible ferromagnetism. Similar results were obtained for Co: TiO2. We show for the first time that charge-compensating oxygen vacancies alone, as predicted by F-center mediated exchange, are not sufficient to activate ferromagnetism. Instead, the onset of ferromagnetism correlates with the presence of structural defects.

UR - http://www.scopus.com/inward/record.url?scp=28844460244&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=28844460244&partnerID=8YFLogxK

U2 - 10.1103/PhysRevLett.95.217203

DO - 10.1103/PhysRevLett.95.217203

M3 - Article

VL - 95

JO - Physical Review Letters

JF - Physical Review Letters

SN - 0031-9007

IS - 21

M1 - 217203

ER -