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Suppression of asymmetric differential resistance in non-Fermi liquid system YbCu_(5-x)Al_(x) (x = 1.3 - 1.75) in high magnetic fields

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 نشر من قبل Gabriel Pristas
 تاريخ النشر 2009
  مجال البحث فيزياء
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The non-Fermi liquid system (NFL) YbCu_(5-x)Al_(x) (x = 1.3 - 1.75) has been investigated in hetero- as well as homo-contact arrangement in magnetic fields up to 22.5 T. The observed dV/dI(V) characteristics reveal asymmetry in hetero-contact arrangement and do not agree with the model of thermal contact heating, at least close to zero-bias voltage. In the case of a hetero-contact arrangement we have observed a maximum at only one voltage polarity at about 1.3 mV (for x = 1.5), which asymmetry is suppressed in an applied magnetic field. This behavior is connected with NFL properties of studied compounds.



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