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Magnetic field-tuned superconductor/insulator transition in TiN nanostrips

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 نشر من قبل Christoph Strunk
 تاريخ النشر 2018
  مجال البحث فيزياء
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We have measured the electric transport properties of TiN nanostrips with different widths. At zero magnetic field the temperature dependent resistance R(T) saturates at a finite resistance towards low temperatures, which results from quantum phase slips in the narrower strips. We find that the current-voltage (I-V) characteristics of the narrowest strips are equivalent to those of small Josephson junctions. Applying a transverse magnetic field drives the devices into a reentrant insulating phase, with I-V-characteristics dual to those in the superconducting regime. The results evidence that our critically disordered superconducting nanostrips behave like small self-organized random Josephson networks.



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