Validation of a quantized-current source with 0.2 ppm uncertainty

Research paper by Friederike Stein, Dietmar Drung, Lukas Fricke, Hansjörg Scherer, Frank Hohls, Christoph Leicht, Martin Götz, Christian Krause, Ralf Behr, Eckart Pesel, Klaus Pierz, Uwe Siegner, Franz-Josef Ahlers, Hans W. Schumacher

Indexed on: 19 Jun '15Published on: 19 Jun '15Published in: Physics - Mesoscopic Systems and Quantum Hall Effect


We report on high-accuracy measurements of quantized current, sourced by a tunable-barrier single-electron pump at frequencies $f$ up to $1$ GHz. The measurements were performed with a new picoammeter instrument, traceable to the Josephson and quantum Hall effects. Current quantization according to $I=ef$ with $e$ the elementary charge was confirmed at $f=545$ MHz with a total relative uncertainty of 0.2 ppm, improving the state of the art by about a factor of 5. For the first time, the accuracy of a possible future quantum current standard based on single-electron transport was experimentally validated to be better than the best realization of the ampere within the present SI.