Unconventional Bulk Superconductivity in YFe_{2}Ge_{2} Single Crystals.

  title={Unconventional Bulk Superconductivity in YFe\_\{2\}Ge\_\{2\} Single Crystals.},
  author={Jiasheng Chen and Monika B. Gamża and J. Banda and Keiron Murphy and James Tarrant and Manuel Brando and F. Malte Grosche},
  journal={Physical review letters},
  volume={125 23},
Sharp superconducting transition anomalies observed in a new generation of single crystals establish that bulk superconductivity is intrinsic to high purity YFe_{2}Ge_{2}. Low temperature heat capacity measurements suggest a disorder and field dependent residual Sommerfeld coefficient, consistent with disorder-induced in-gap states as expected for a sign-changing order parameter. The sevenfold reduction in disorder scattering in these new crystals to residual resistivities ≃0.45  μΩ cm was… Expand

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