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Ballistic Intrinsic Spin-Hall Effect in HgTe Nanostructures

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 نشر من قبل Dr. H. Buhmann
 تاريخ النشر 2008
  مجال البحث فيزياء
والبحث باللغة English
 تأليف C. Bruene




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We report the first electrical manipulation and detection of the mesoscopic intrinsic spin-Hall effect (ISHE) in semiconductors through non-local electrical measurement in nano-scale H-shaped structures built on high mobility HgTe/HgCdTe quantum wells. By controlling the strength of the spin-orbit splittings and the n-type to p-type transition by a top-gate, we observe a large non-local resistance signal due to the ISHE in the p-regime, of the order of kOhms, which is several orders of magnitude larger than in metals. In the n-regime, as predicted by theory, the signal is at least an order of magnitude smaller. We verify our experimental observation by quantum transport calculations which show quantitative agreement with the experiments.



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