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Strain-induced large spin splitting and persistent spin helix at LaAlO$_3$/SrTiO$_3$ interface

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 نشر من قبل Naoya Yamaguchi
 تاريخ النشر 2017
  مجال البحث فيزياء
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We investigated the effect of the tensile strain on the spin splitting at the n-type interface in LaAlO$_3$/SrTiO$_3$ in terms of the spin-orbit coupling coefficient $alpha$ and spin texture in the momentum space using first-principles calculations. We found that the $alpha$ could be controlled by the tensile strain and be enhanced up to 5 times for the tensile strain of 7%, and the effect of the tensile strain leads to a persistent spin helix, which has a long spin lifetime. These results support that the strain effect on LaAlO$_3$/SrTiO$_3$ is important for various applications such as spinFET and spin-to-charge conversion.



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