Universal energy-level statistics for disordered metals

We study the spectral fluctuations for two-dimensional random systems with spin-orbit coupling in the ‘‘mesoscopic’’ conducting regime. The results for the nearest-level spacing distribution function and the Dyson ${\Delta }_3$ statistics are consistent with the properties of level repulsion and spectral rigidity common in Wigner-Dyson ensembles. The origin of the apparent universality for random tight-binding matrix ensembles is conjectured and its implications for two-dimensional quantum transport and the universal conductance fluctuations are discussed.