Mesoscopic Coulomb blockade in one-channel quantum dots

Signatures of "mesoscopic Coulomb blockade" are reported for quantum dots w ith one fully transmitting point-contact lead; T-1 = 1,T-2 much less than 1 . Unlike the Coulomb blockade (CB) in weak-tunneling devices (T-1, T-2 much less than 1), one-channel CB is a mesoscopic effect requiring quantum cohe rence. Several distinctive features of mesoscopic CB are observed, includin g a reduction in CB upon breaking time-reversal symmetry with a magnetic fi eld, relatively large fluctuations of peak position as a function of magnet ic field, and strong temperature dependence on the scale of the quantum lev el spacing.