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arXiv · 1104.1072

Improved tunneling magnetoresistance at low temperature in manganite junctions grown by molecular beam epitaxy

Robert Werner·Alexandr Yu. Petrov·Lucero Alvarez Mino·Reinhold Kleiner·Dieter Koelle·Bruce A. Davidson
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Abstract

We report resistance versus magnetic field measurements for a La0.65Sr0.35MnO3/SrTiO3/La0.65Sr0.35MnO3 tunnel junction grown by molecular-beam epitaxy, that show a large field window of extremely high tunneling magnetoresistance (TMR) at low temperature. Scanning the in-plane applied field orientation through 360^/circ, the TMR shows 4-fold symmetry, i.e. biaxial anisotropy, aligned with the crystalline axes but not the junction geometrical long axis. The TMR reaches ~ 1900% at 4K, corresponding to an interfacial spin polarization of > 95% assuming identical interfaces. These results show that uniaxial anisotropy is not necessary for large TMR, and lay the groundwork for future improvements in TMR in manganite junctions.

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Robert Werner, Alexandr Yu. Petrov, Lucero Alvarez Mino, Reinhold Kleiner, Dieter Koelle, Bruce A. Davidson. 2011-04-06. Improved tunneling magnetoresistance at low temperature in manganite junctions grown by molecular beam epitaxy. https://doi.org/10.1063/1.3581885

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