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

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 نشر من قبل Mahn-Soo Choi
 تاريخ النشر 2014
  مجال البحث فيزياء
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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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