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Phase slip lines in superconducting few-layer NbSe$_2$ crystals

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 نشر من قبل Nicola Paradiso
 تاريخ النشر 2018
  مجال البحث فيزياء
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We show the results of two-terminal and four-terminal transport measurements on few-layer NbSe$_2$ devices at large current bias. In all the samples measured, transport characteristics at high bias are dominated by a series of resistance jumps due to nucleation of phase slip lines, the two dimensional analogue of phase slip centers. In point contact devices the relatively simple and homogeneous geometry enables a quantitative comparison with the model of Skocpol, Beasley and Tinkham. In extended crystals the nucleation of a single phase slip line can be induced by mechanical stress of a region whose width is comparable to the charge imbalance equilibration length.



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