Transparent Semiconductor-Superconductor Interface and Induced Gap in an Epitaxial Heterostructure Josephson Junction

@article{Kjaergaard2016TransparentSI,
  title={Transparent Semiconductor-Superconductor Interface and Induced Gap in an Epitaxial Heterostructure Josephson Junction},
  author={Morten Kjaergaard and Henri J. Suominen and Michał P Nowak and A. Akhmerov and Javad Shabani and Chris J. Palmstr{\o}m and Fabrizio Nichele and Charles M. Marcus},
  journal={arXiv: Mesoscale and Nanoscale Physics},
  year={2016}
}
Measurement of multiple Andreev reflection (MAR) in a Josephson junction made from an InAs heterostructure with epitaxial aluminum is used to quantify the highly transparent semiconductor-superconductor interface, indicating near-unity transmission. The observed temperature dependence of MAR does not follow a conventional BCS form, but instead agrees with a model in which the density of states in the quantum well acquires an effective induced gap, in our case 180 {\mu}eV, close to that of the… 

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