Coulomb charging at large conduction

We discuss the suppression of Coulomb charging effects on a small metallic island coupled to an electrode by a tunnel junction. At high temperatures the quantum corrections to the classical charging energy Ec=e²/2C, where C is the island capacitance, are evaluated. At low temperatures the large quantum fluctuations of the island charge cause a strong reduction of the effective Ec, which is determined explicitly in the limit of a large tunneling conductance. {} 1996 The American Physical Society.