  We consider an interacting quantum dot working as a coherent source of single
electrons. The dot is tunnel coupled to a reservoir and capacitively coupled to
a gate terminal with an applied ac potential. At low frequencies, this is the
quantum analog of the RC circuit with a purely dynamical response. We
investigate the quantized dynamics as a consequence of ac pulses with large
amplitude. Within a Keldysh-Green function formalism we derive the
time-dependent current in the Coulomb blockade regime. Our theory thus extends
previous models that considered either noninteracting electrons in nonlinear
response or interacting electrons in the linear regime. We prove that the
electron emission and absorption resonances undergo a splitting when the
charging energy is larger than the tunnel broadening. For very large charging
energies, the additional peaks collapse and the original resonances are
recovered, though with a reduced amplitude. Quantization of the charge emitted
by the capacitor is reduced due to Coulomb repulsion and additional plateaus
arise. Additionally, we discuss the differential capacitance and resistance as
a function of time. We find that to leading order in driving frequency the
current can be expressed as a weighted sum of noninteracting currents shifted
by the charging energy.
