Upper critical field in electron-doped cuprate superconductor   Nd$_{2-x}$Ce$_x$CuO$_{4+\delta}$: two-gap model
  We present resistivity measurements of the upper critical field (H$_{c2}$) phase diagram as a function of temperature (T) for Nd$_{1.85}$Ce$_{0.15}$CuO$_{4+\delta}$/SrTiO$_3$ single crystal films with different degree of disorder ($\delta$) in magnetic fields up to 90 kOe at temperatures down to 0.4 K. The data are well described by a two-band/two-gap model for a superconductor in the dirty limit. 
T. B.Charikova, N. G. Shelushinina, G. I. Harus, D. S. Petukhov, V. N.   Neverov, A. A. Ivanov
cond-mat.supr-con