Non-thermal origin of nonlinear transport across magnetically induced   superconductor-metal-insulator transition
  We have studied the effect of perpendicular magnetic fields and temperatures on the nonlinear electronic transport in amorphous Ta superconducting thin films. The films exhibit a magnetic field induced metallic behavior intervening the superconductor-insulator transition in the zero temperature limit. We show that the nonlinear transport in the superconducting and metallic phase is of non-thermal origin and accompanies an extraordinarily long voltage response time. 
Y. Seo, Y. Qin, C. L. Vicente, K. S. Choi, and Jongsoo Yoon