Spectroscopic evidence of odd frequency superconducting order

  title={Spectroscopic evidence of odd frequency superconducting order},
  author={Avradeep Pal and Jabir Ali Ouassou and M Eschrig and Jacob Linder and Mark G. Blamire},
  journal={Scientific Reports},
Spin filter superconducting S/I/N tunnel junctions (NbN/GdN/TiN) show a robust and pronounced Zero Bias Conductance Peak (ZBCP) at low temperatures, the magnitude of which is several times the normal state conductance of the junction. Such a conductance anomaly is representative of unconventional superconductivity and is interpreted as a direct signature of an odd frequency superconducting order. 
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