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Magnetic effects at the interface between nonmagnetic oxides

A. Brinkman·M. Huijben·M. van Zalk·J. Huijben·U. Zeitler·J. C. Maan·W. G. van der Wiel·G. Rijnders·D. H. A. Blank·H. Hilgenkamp
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Abstract

The electronic reconstruction at the interface between two insulating oxides can give rise to a highly-conductive interface. In analogy to this remarkable interface-induced conductivity we show how, additionally, magnetism can be induced at the interface between the otherwise nonmagnetic insulating perovskites SrTiO3 and LaAlO3. A large negative magnetoresistance of the interface is found, together with a logarithmic temperature dependence of the sheet resistance. At low temperatures, the sheet resistance reveals magnetic hysteresis. Magnetic ordering is a key issue in solid-state science and its underlying mechanisms are still the subject of intense research. In particular, the interplay between localized magnetic moments and the spin of itinerant conduction electrons in a solid gives rise to intriguing many-body effects such as Ruderman-Kittel-Kasuya-Yosida (RKKY) interactions, the Kondo effect, and carrier-induced ferromagnetism in diluted magnetic semiconductors. The conducting oxide interface now provides a versatile system to induce and manipulate magnetic moments in otherwise nonmagnetic materials.

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A. Brinkman, M. Huijben, M. van Zalk, J. Huijben, U. Zeitler, J. C. Maan, W. G. van der Wiel, G. Rijnders, D. H. A. Blank, H. Hilgenkamp. 2007-06-04. Magnetic effects at the interface between nonmagnetic oxides. https://doi.org/10.1038/nmat1931

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