ANOMALOUS DIFFUSION NEAR THE FLUX LATTICE MELTING TRANSITION IN HIGH-TC SUPERCONDUCTORS

The authors consider the dissipation arising from the activated motion of a flux line lattice in the presence of dilute pinning centres. By regarding this process as an effective motion of the pins relative to the flux lattice, they map the problem into the diffusion process of a particle interacting with the flux line lattice. They solve this problem analytically using a novel microscopic diffusion theory. In particular, they show that anomalous behaviour of the linear resistivity is expected at the flux lattice melting, and may show up as a dip in its temperature dependence.