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Title: Magnetic Semiconducting Anatase TiO2_d Grown on (1 0 0) LaAlO3 Having Magnetic Order up to 880K

Abstract

We demonstrate a semiconducting material, TiO{sub 2-{delta}}, with magnetism up to 880 K, without the introduction of magnetic ions. The magnetism in these films stems from the controlled introduction of anion defects from both the film substrate interface as well as processing under a deficient oxygen atmosphere. First-principle band structure calculations indicate that the exchange between Ti cations mediated by an oxygen anion is positive, i.e., ferromagnetic, whereas the exchange between cations via a vacancy is negative, i.e., ferrimagnetic. It is likely that both the mechanisms are active in this system. This represents a new and promising approach in the search for room-temperature magnetic semiconductors.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
930550
Report Number(s):
BNL-80661-2008-JA
Journal ID: ISSN 0304-8853; JMMMDC; TRN: US200904%%782
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Magnetism and Magnetic Materials; Journal Volume: 309
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AMBIENT TEMPERATURE; ANIONS; CATIONS; DEFECTS; ELECTRONIC STRUCTURE; FILMS; MAGNETIC SEMICONDUCTORS; MAGNETISM; OXYGEN; PROCESSING; SEMICONDUCTOR MATERIALS; SUBSTRATES; TITANIUM OXIDES; VACANCIES; national synchrotron light source

Citation Formats

Yoon,S., Chen, Y., Yang, A., Goodrich, T., Zuo, X., Ziemer, K., Vittoria, C., and Harris, V. Magnetic Semiconducting Anatase TiO2_d Grown on (1 0 0) LaAlO3 Having Magnetic Order up to 880K. United States: N. p., 2007. Web. doi:10.1016/j.jmmm.2006.05.014.
Yoon,S., Chen, Y., Yang, A., Goodrich, T., Zuo, X., Ziemer, K., Vittoria, C., & Harris, V. Magnetic Semiconducting Anatase TiO2_d Grown on (1 0 0) LaAlO3 Having Magnetic Order up to 880K. United States. doi:10.1016/j.jmmm.2006.05.014.
Yoon,S., Chen, Y., Yang, A., Goodrich, T., Zuo, X., Ziemer, K., Vittoria, C., and Harris, V. Mon . "Magnetic Semiconducting Anatase TiO2_d Grown on (1 0 0) LaAlO3 Having Magnetic Order up to 880K". United States. doi:10.1016/j.jmmm.2006.05.014.
@article{osti_930550,
title = {Magnetic Semiconducting Anatase TiO2_d Grown on (1 0 0) LaAlO3 Having Magnetic Order up to 880K},
author = {Yoon,S. and Chen, Y. and Yang, A. and Goodrich, T. and Zuo, X. and Ziemer, K. and Vittoria, C. and Harris, V.},
abstractNote = {We demonstrate a semiconducting material, TiO{sub 2-{delta}}, with magnetism up to 880 K, without the introduction of magnetic ions. The magnetism in these films stems from the controlled introduction of anion defects from both the film substrate interface as well as processing under a deficient oxygen atmosphere. First-principle band structure calculations indicate that the exchange between Ti cations mediated by an oxygen anion is positive, i.e., ferromagnetic, whereas the exchange between cations via a vacancy is negative, i.e., ferrimagnetic. It is likely that both the mechanisms are active in this system. This represents a new and promising approach in the search for room-temperature magnetic semiconductors.},
doi = {10.1016/j.jmmm.2006.05.014},
journal = {Journal of Magnetism and Magnetic Materials},
number = ,
volume = 309,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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