We consider an interacting quantum dot working as a coherent source of singleelectrons. The dot is tunnel coupled to a reservoir and capacitively coupled toa gate terminal with an applied ac potential. At low frequencies, this is thequantum analog of the RC circuit with a purely dynamical response. Weinvestigate the quantized dynamics as a consequence of ac pulses with largeamplitude. Within a Keldysh-Green function formalism we derive thetime-dependent current in the Coulomb blockade regime. Our theory thus extendsprevious models that considered either noninteracting electrons in nonlinearresponse or interacting electrons in the linear regime. We prove that theelectron emission and absorption resonances undergo a splitting when thecharging energy is larger than the tunnel broadening. For very large chargingenergies, the additional peaks collapse and the original resonances arerecovered, though with a reduced amplitude. Quantization of the charge emittedby the capacitor is reduced due to Coulomb repulsion and additional plateausarise. Additionally, we discuss the differential capacitance and resistance asa function of time. We find that to leading order in driving frequency thecurrent can be expressed as a weighted sum of noninteracting currents shiftedby the charging energy.
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