NEW UNIVERSALITY CLASS AT THE SUPERCONDUCTOR-INSULATOR TRANSITION

We study transport properties of thin films near the superconductor-in sulator transition. Formulated in a phase representation, the key new feature of our model is the assumption of a local Ohmic dissipative me chanism. Coarse graining leads to a Ginzburg-Landau description, with non-Ohmic dynamics for the order parameter. For strong enough damping a new universality class is found. It is characterized by a nonunivers al de conductivity, and a damping-dependent dynamical critical exponen t. The formulation also provides a description of the magnetic-field-t uned transition. Several microscopic mechanisms are proposed as the or igin of the dissipation.