Quantum Coulomb Blockade in Chaotic Systems

We study the Coulomb blockade in a chaotic cavity connected to a lead by a perfectly transmitting quantum channel. In contrast to the previous theories, we show that the quantum fluctuations of charge, resulting from the perfect transmission, do not destroy the Coulomb blockade completely. The oscillatory dependence of all the observable characteristics on the gate voltage persists, its period is not affected; however, phases of the oscillations are random, reflecting the chaotic electron motion in the cavity. Because of this randomness, the Coulomb blockade shows up not in the averages but in the correlation functions of the fluctuating observables (e.g., capacitance or tunneling conductance).