Subgap resonant quasiparticle transport in normal-superconductor quantum dot devices

  title={Subgap resonant quasiparticle transport in normal-superconductor quantum dot devices},
  author={Jorg Gramich and Andreas Baumgartner and Christian Schonenberger},
  journal={arXiv: Mesoscale and Nanoscale Physics},
We report thermally activated transport resonances for biases below the superconducting energy gap in a carbon nanotube (CNT) quantum dot (QD) device with a superconducting Pb and a normal metal contact. These resonances are due to the superconductor's finite quasi-particle population at elevated temperatures and can only be observed when the QD life-time broadening is considerably smaller than the gap. This condition is fulfilled in our QD devices with optimized Pd/Pb/In multi-layer contacts… 

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