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arXiv · 1911.05675

A resistance bridge based on a cryogenic current comparator achieving sub-$10^{-9}$ measurement uncertainties

W. Poirier·D. Leprat·F. Schopfer
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Abstract

A new resistance bridge has been built at the Laboratoire national de m\'etrologie et d'essais (LNE) to improve the ohm realization in the $Syst\`eme International$ (SI) of units from the quantum Hall effect. We describe the instrument, the performance of which relies on two synchronized and noise-filtered current sources, an accurate and stable current divider and a cryogenic current comparator (CCC) having a low noise of $\mathrm{80~pA.t/Hz^{1/2}}$. The uncertainty budget for the measurement of the 100 $\Omega/(R_\mathrm{K}/2)$ ratio, where $R_\mathrm{K}$ is the von Klitzing constant, amounts to a few parts in $10^{10}$ only.

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W. Poirier, D. Leprat, F. Schopfer. 2019-11-13. A resistance bridge based on a cryogenic current comparator achieving sub-$10^{-9}$ measurement uncertainties. https://arxiv.org/abs/1911.05675

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