Realisation of a quantum current standard at liquid helium temperature with sub-ppm reproducibility

Research output: Contribution to journalArticleScientificpeer-review


  • Stephen Giblin
  • Emma Mykkanen
  • Antti Kemppinen
  • Pekka Immonen
  • Antti Manninen
  • Mate Jenei
  • Mikko Mottonen
  • Gento Yamahata
  • Akira Fujiwara
  • Masaya Kataoka

Research units

  • National Physical Laboratory
  • Nippon Telegraph and Telephone Corporation
  • VTT Technical Research Centre of Finland


A silicon electron pump operating at the temperature of liquid helium has demonstrated repeatable operation with sub-ppm accuracy. The pump current, approximately 168 pA, is measured by three laboratories, and the measurements agree with the expected current ef within the uncertainties which range from 0.2 ppm to 1.3 ppm. All the measurements are carried out in zero applied magnetic field, and the pump drive signal is a sine wave. The combination of simple operating conditions with high accuracy demonstrates the possibility that an electron pump can operate as a current standard in a National Measurement Institute. We also discuss other practical aspects of using the electron pump as a current standard, such as testing its robustness to changes in the control parameters, and using a rapid tuning procedure to locate the optimal operation point.


Original languageEnglish
Article number025013
Number of pages8
Issue number2
Publication statusPublished - Apr 2020
MoE publication typeA1 Journal article-refereed

    Research areas

  • electron pump, quantised charge pumping, SI base units

ID: 41984116