Depairing field, onset temperature and the nature of the transition in   cuprates
  The depairing (upper critical) field $H_{c2}$ in hole-doped cuprates has been inferred from magnetization curves $M$-$H$ measured by torque magnetometry in fields $H$ up to 45 T. We discuss the implications of the results for the pair binding energy, the Nernst onset temperature, fluctuations and the nature of the Meissner transition at $T_c$. 
Lu Li, Yayu Wang, J. G. Checkelsky, M. J. Naughton, Seiki Komiya,   Shimpei Ono, Yoichi Ando and N. P. Ong