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arXiv · 1109.1274

Upper limit to magnetism in LaAlO3/SrTiO3 heterostructures

M. R. Fitzsimmons·N. Hengartner·S. Singh·M. Zhernenkov·F. Y. Bruno·J. Santamaria·A. Brinkman·M. Huijben·H. Molegraaf·J. de la Venta·Ivan K. Schuller
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Abstract

Using polarized neutron reflectometry (PNR) we measured the neutron spin dependent reflectivity from four LaAlO3/SrTiO3 superlattices. This experiment implies that the upper limit for the magnetization induced by an 11 T magnetic field at 1.7 K is 2 emu/cm3. SQUID magnetometry of the superlattices sporadically finds an enhanced moment, possibly due to experimental artifacts. These observations set important restrictions on theories which imply a strongly enhanced magnetism at the interface between LaAlO3 and SrTiO3.

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M. R. Fitzsimmons, N. Hengartner, S. Singh, M. Zhernenkov, F. Y. Bruno, J. Santamaria, A. Brinkman, M. Huijben, H. Molegraaf, J. de la Venta, Ivan K. Schuller. 2011-09-06. Upper limit to magnetism in LaAlO3/SrTiO3 heterostructures. https://doi.org/10.1103/physrevlett.107.217201

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