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Vorticity induced negative nonlocal resistance in viscous two-dimensional electron system

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 نشر من قبل Gennady Gusev M
 تاريخ النشر 2018
  مجال البحث فيزياء
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We report non-local electrical measurements in a mesoscopic size two-dimensional (2D) electron gas in a GaAs quantum well in a hydrodynamic regime. Viscous electric flow is expected to be dominant when electron-electron collisions occur more often than the impurity or phonon scattering events. We observe a negative nonlocal resistance and attribute it to the formation of whirlpools in the electron flow. We use the different nonlocal transport geometries and compare the results with a theory demonstrating the significance of hydrodynamics in mesoscopic samples.



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