Rectification artefacts in the tunable-barrier electron pump
Download (PDF 3.08 MB)
NPL has developed a novel form of clock-controlled single electron device - the tunable barrier electron pump.
This is a promising candidate for a quantum current standard and has a demonstrated accuracy better than a few parts per million. In this work, we consider the possibility of errors in these pumps due to classical rectification. This can arise from the combination of parasitic pick-up of the time varying gate signal combined with variations in device conductance during the pumping cycle. We develop and test a model for the rectified current, and show that the errors, for the device tested, are smaller than 1 part in 10^8 of the pump current.