Accuracy of the single-electron pump using an optimized step-like rf drive waveform

We have performed an optimization of those parameters of a single-electron pump that may influence the accuracy of this device as a standard of de current. Two types of rf drive were considered: the traditional triangular waveform and a step-like waveform. We have shown that, after optimization, the accuracy of the pump may be improved considerably in a wide range of drive frequencies, especially at low temperatures, using the step-like waveform. For example, the error of a five-junction pump with junction capacitances C = 0.1 fF at 100 mK and 10 MHz maybe as small as 10(-13). (C) 1996 American Institute of Physics.