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Spin-orbit coupling induced by a mass gradient

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 نشر من قبل Alex Matos-Abiague
 تاريخ النشر 2010
  مجال البحث فيزياء
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 تأليف A. Matos-Abiague




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The existence of a spin-orbit coupling (SOC) induced by the gradient of the effective mass in low-dimensional heterostructures is revealed. In structurally asymmetric quasi-two-dimensional semiconductor heterostructures the presence of a mass gradient across the interfaces results in a SOC which competes with the SOC created by the electric field in the valence band. However, in graded quantum wells subjected to an external electric field, the mass-gradient induced SOC can be finite even when the electric field in the valence band vanishes.



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