MESOSCOPIC FLUCTUATIONS OF ELASTIC COTUNNELING

We study mesoscopic fluctuations of the conductance through a quantum dot at the wings of the Coulomb blockade peaks. At low temperatures, t he main mechanism of conduction is elastic cotunneling. The conductanc e strongly fluctuates with an applied magnetic field. The magnetic cor relation field is shown to be controlled by the charging energy, and t he correlation function has a universal form. The distribution functio n for the conductance obtained analytically shows a nontrivial crossov er between the orthogonal and unitary ensembles.