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arXiv · 1409.6374

Negative Tunneling Magneto-Resistance in Quantum Wires with Strong Spin-Orbit Coupling

Seungju Han·Llorens Serra·Mahn-Soo Choi
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Abstract

We consider a two-dimensional magnetic tunnel junction of the FM/I/QW(FM+SO)/I/N structure, where FM, I and QW(FM+SO) stand for a ferromagnet, an insulator and a quantum wire (QW) with both magnetic ordering and Rashba spin-orbit (SOC), respectively. The tunneling magneto-resistance (TMR) exhibits strong anisotropy and switches sign as the polarization direction varies relative to the QW axis, due to interplay among the one-dimensionality, the magnetic ordering, and the strong SOC of the QW. The results may provide a possible explanation for the sign-switching anisotropic TMR recently observed in the LaAlO$_3$/SrTiO$_3$ interface.

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Seungju Han, Llorens Serra, Mahn-Soo Choi. 2014-09-23. Negative Tunneling Magneto-Resistance in Quantum Wires with Strong Spin-Orbit Coupling. https://doi.org/10.1088/0953-8984/27/25/255002

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