Coulomb blockade and partially transparent tunneling barriers in the quantum Hall regime

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Abstract
Recently Coulomb-blockade oscillations were observed in conductance through a quantum dot in a regime where some channels are transmitted adiabatically [B. W. Alphenaar et al., Phys. Rev. B 46, 7236 (1992)]. The self-consistent model introduced by McEuen, ourselves, and co-workers [P. L. McEuen et al., Phys. Rev. B 45, 11 419 (1992)] is extended to the case of a dot with partially transparent barriers. We find that the adiabatically transmitted channels strongly influence the conductance oscillations by screening the Coulomb interaction between states confined to the dot. Using the self-consistent model as a starting point, we develop an effective-capacitance model of the Coulomb blockade, where the adiabatically transmitted channels act as additional capacitances for states confined in the dot. We also address excited states within the framework of the self-consistent model, and discuss the dynamics of transport in the presence of adiabatically transmitted edge channels.