Coulomb Blockade in Metallic Grains at Large Conductance

We study Coulomb blockade effects in the thermodynamic quantities of a weakly disordered metallic grain coupled to a metallic lead by a tunneling contact with a large conductance $g_T$. We consider the case of broken time-reversal symmetry and obtain expressions for both the ensemble averaged amplitude of the Coulomb blockade oscillations of the thermodynamic potential and the correlator of its mesoscopic fluctuations for a finite mean level space $delta$ in the grain. 

We develop a novel method which allows for an exact evaluation of the functional integral arising from disorder averaging. The results and the method are applicable in the temperature range $delta << T << E_C$.