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Anomalous spin-resolved point-contact transmission of holes due to cubic Rashba spin-orbit coupling

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 نشر من قبل Stefano Chesi
 تاريخ النشر 2010
  مجال البحث فيزياء
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Evidence is presented for the finite wave vector crossing of the two lowest one-dimensional spin-split subbands in quantum point contacts fabricated from two-dimensional hole gases with strong spin-orbit interaction. This phenomenon offers an elegant explanation for the anomalous sign of the spin polarization filtered by a point contact, as observed in magnetic focusing experiments. Anticrossing is introduced by a magnetic field parallel to the channel or an asymmetric potential transverse to it. Controlling the magnitude of the spin-splitting affords a novel mechanism for inverting the sign of the spin polarization.



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