Practical Analysis of Single Electron Pump with Harmonic Drive

We study a two-gate single electron pump device with harmonic AC gate voltages. We have performed numerical and analytical calculations of quantum correction to a DC current due to the cotunneling phenomena. This correction determines the accuracy of the device in a wide range of parameters (temperature, frequency and amplitude of the gate voltage modulation). We found the crossover from adiabatic transport at lower frequencies f ≪ f cr to non-adiabatic transport at higher frequencies f ≫ f cr . The crossover frequency f cr = { k B T / ( e 2 / C ) } 2 / ( A R T C ) is argued to be the optimal frequency of the pump operation.