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Non-monotonic magnetoresistance of two-dimensional electron systems in the ballistic regime

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 نشر من قبل Alexander Kuntsevich
 تاريخ النشر 2009
  مجال البحث فيزياء
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We report experimental observations of a novel magnetoresistance (MR) behavior of two-dimensional electron systems in perpendicular magnetic field in the ballistic regime, for k_BTtau/hbar>1. The MR grows with field and exhibits a maximum at fields B>1/mu, where mu is the electron mobility. As temperature increases the magnitude of the maximum grows and its position moves to higher fields. This effect is universal: it is observed in various Si- and GaAs- based two-dimensional electron systems. We compared our data with recent theory based on the Kohn anomaly modification in magnetic field, and found qualitative similarities and discrepancies.



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