A capacitance standard based on counting electrons.

Science

National Institute of Standards and Technology, Boulder, CO 80303, USA. National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.

Published: September 1999

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 DeltaV was measured. Repeated measurements of C = Ne/DeltaV 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.

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http://dx.doi.org/10.1126/science.285.5434.1706DOI Listing

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