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Counting Errors in a Voltage-Biased Electron Pump



Xavier Jehl, Mark W. Keller, Richard L. Kautz, Joe Aumentado, John M. Martinis


We have measured the counting errors of a 7-junction electron pump when charge is pumped against a voltage difference. At voltages above about 50 υV, we find that the errors increase exponentially with both pump voltage and temperature, in agreement with theoretical predictions. To compare experiment and simulation, all pump parameters were determined by independent electron-box experiments. Although we assumed temperatures somewhat higher than those measured, simulations based on the ground-capacitance model yield excellent quantitative agreement with experiment and indicate that errors in the high-voltage regime are due to thermally activated tunneling. In addition, a surprising asymmetry between positive and negative voltages is explained by an asymmetry in the junction capacitances. Our results are important to the application of pumps as capacitance standards.
Physical Review B (Condensed Matter and Materials Physics)


capacitance standard, electron pump, single-electron tunneling


Jehl, X. , Keller, M. , Kautz, R. , Aumentado, J. and Martinis, J. (2003), Counting Errors in a Voltage-Biased Electron Pump, Physical Review B (Condensed Matter and Materials Physics), [online], (Accessed July 25, 2024)


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Created April 29, 2003, Updated October 12, 2021