Proximity-induced gap in nanowires with a thin superconducting shell

  title={Proximity-induced gap in nanowires with a thin superconducting shell},
  author={Thomas Kiendl and Felix von Oppen and Piet W. Brouwer},
  journal={Physical Review B},
Coupling a normal metal wire to a superconductor induces an excitation gap in the normal metal. In the absence of disorder, the induced excitation gap is strongly suppressed by finite-size effects if the thickness of the superconductor is much smaller than the thickness of the normal metal and the superconducting coherence length. We show that the presence of disorder, either in the bulk or at the exposed surface of the superconductor, significantly enhances the magnitude of the induced gap… 

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