Induced transparency in EXAFS as cuprate superconductors go through Tc
  The increased transmission, observed in the EXAFS region of their X-ray absorption spectra, as cuprate materials go through the superconducting transition temperature Tc is correlated with an increase in Abrikosov Vortex expulsion in zero magnetic field as the temperature T approaches Tc. 
J. G. Chigvinadze, G. I. Mamniashvilli, J.V. Acrivos