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Electric Field Effect in Diluted Magnetic Insulator Anatase Co:TiO2

T. Zhao·S. R. Shinde·S. B. Ogale·H. Zheng·T. Venkatesan·R. Ramesh·S. Das Sarma
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Abstract

An external electric field induced reversible modulation of room temperature magnetic moment is achieved in an epitaxial and insulating thin film of dilutely cobalt-doped anatase TiO2. This first demonstration of electric field effect in any oxide based diluted ferromagnet is realized in a high quality epitaxial heterostructure of PbZr0.2Ti0.8O3/Co:TiO2/SrRuO3 grown on (001) LaAlO3. The observed effect, which is about 15% in strength in a given heterostructure, can be modulated over several cycles. Possible mechanisms for electric field induced modulation of insulating ferromagnetism are discussed.

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T. Zhao, S. R. Shinde, S. B. Ogale, H. Zheng, T. Venkatesan, R. Ramesh, S. Das Sarma. 2004-04-07. Electric Field Effect in Diluted Magnetic Insulator Anatase Co:TiO2. https://doi.org/10.1103/physrevlett.94.126601

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