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Valley susceptibility of an interacting two-dimensional electron system

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 نشر من قبل Oki Gunawan
 تاريخ النشر 2006
  مجال البحث فيزياء
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We report direct measurements of the valley susceptibility, the change of valley population in response to applied symmetry-breaking strain, in an AlAs two-dimensional electron system. As the two-dimensional density is reduced, the valley susceptibility dramatically increases relative to its band value, reflecting the systems strong electron-electron interaction. The increase has a remarkable resemblance to the enhancement of the spin susceptibility and establishes the analogy between the spin and valley degrees of freedom.



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