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A Capacitance Standard Based on Counting Electrons



Mark W. Keller, Ali L. Eichenberger, John M. Martinis, Neil M. Zimmerman


A capacitance standard based directly on the definition of capacitance was built. Single-electron tunneling devices were used to place N electrons of charge e onto a cryogenic capacitor C, and the resulting voltage change ΔV was measured. Repeated measurements of C 5 Ne/ΔV with this method have a relative standard deviation of 0.3 x 10^-6. This standard offers a natural basis for capacitance analogous to the Josephson effect for voltage and the quantum Hall effect for resistance.
Science Magazine


Keller, M. , Eichenberger, A. , Martinis, J. and Zimmerman, N. (1999), A Capacitance Standard Based on Counting Electrons, Science Magazine, [online], (Accessed May 29, 2024)


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Created September 10, 1999, Updated August 15, 2018