Current correlations and quantum localization in two-dimensional disordered systems with broken time-reversal invariance

We study long-range correlations of equilibrium current densities in a two-dimensional mesoscopic system with the time-reversal invariance broken by a random or homogeneous magnetic field. Our result is universal, i.e., it does not depend on the type (random potential or random magnetic field) or correlation length of disorder. Performing a closely connected analysis of the quantum correction to the conductivity in one-loop order, we show that it is nondivergent, in contrast to a recent claim in the literature.