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Large two-level magnetoresistance effect in doped manganite grain boundary junctions

J. B. Philipp·C. Hoefener·S. Thienhaus·J. Klein·L. Alff·R. Gross
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Abstract

We performed a systematic analysis of the tunneling magnetoresistance (TMR) effect in single grain boundary junctions formed in epitaxial La(2/3)Ca(1/3)MnO(3) films deposited on SrTiO(3) bicrystals. For magnetic fields H applied parallel to the grain boundary barrier, an ideal two-level resistance switching behavior with sharp transitions is observed with a TMR effect of up to 300% at 4.2 K and still above 100% at 77 K. Varying the angle between H and the grain boundary results in differently shaped resistance vs H curves. The observed behavior is explained within a model of magnetic domain pinning at the grain boundary interface.

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J. B. Philipp, C. Hoefener, S. Thienhaus, J. Klein, L. Alff, R. Gross. 2000-08-07. Large two-level magnetoresistance effect in doped manganite grain boundary junctions. https://doi.org/10.1103/physrevb.62.r9248

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