Finite temperature transport at the superconductor-insulator transition in disordered systems

I argue that the de limit of the universal crossover function for the conductivity at the superconductor-insulator transition in disordered systems is an analytic function of dimensionality of the system d, with a simple pole at d = 1. By combining the exact result for the crossover function in d = 1 with the recursion relations in d = 1 + epsilon, the leading term in the Laurent series in epsilon is computed for the systems of disordered bosons. The universal de critical conductivity for the system with Coulomb interactions in d = 2 is estimated to be similar to 0.69(2e)(2)/h, in satisfactory agreement with many experiments. [S0031-9007(98)07444-4].