Improved Cryogenic Capacitor for the ECCS: Larger Value (10 pF) and SI Measurement by Tuning the Calculable Capacitor

Published

September 4, 2002

Author(s)

Neil M. Zimmerman, Mahmoud A. El-Sabbagh, Yicheng Wang

Abstract

We report on several advances in the development of a cryogenic vacuum-gap capacitor C_cryo, for use with the electron-counting cpacitance standard (ECCS). First, we have increased the value by about a factor of ten, to 10pF; this will both make the ECCS more useful as a commercial standard, and also allows a substantial reduction in the relative uncertainty of the calibration of C_cryo. Second, the capacitor's stability is excellent, with a drift less than 10^-9/hour. This stability is required for the third advance: we have succeeded in tuning the calculable capacitor, which allows us to make a measurement of C_cryo in SI units, without requiring a precise value of C_cryo. We demonstrate such a measurement, with an uncertainty of about 3 x 10^-8.

Citation

IEEE Transactions on Instrumentation and Measurement

Pub Type

Journals

Keywords

cryogenic vacuum-gap capacitor, tuning the calculable capacitor

Citation

Zimmerman, N. , El-Sabbagh, M. and Wang, Y. (2002), Improved Cryogenic Capacitor for the ECCS: Larger Value (10 pF) and SI Measurement by Tuning the Calculable Capacitor, IEEE Transactions on Instrumentation and Measurement (Accessed October 27, 2025)