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arXiv · 1808.09741

Inter-laboratory nanoamp current comparison with sub-part-per-million uncertainty

Stephen Giblin·Dietmar Drung·Martin Goetz·Hansjoerg Scherer
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Abstract

An ultrastable low-noise current amplifier (ULCA) has been transferred between two laboratories, NPL and PTB, four times, with three of the transfers yielding a relative change in the trans-resistance gain of less than $2 \times 10^{-7}$. This is a new bench-mark for inter-laboratory transfer of small current. We describe in detail the use of a cryogenic current comparator to calibrate the ULCA at NPL, and the use of the ULCA to measure $1$ G$\Omega$ resistors with relative uncertainties at the $10^{-7}$ level.

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Stephen Giblin, Dietmar Drung, Martin Goetz, Hansjoerg Scherer. 2018-08-29. Inter-laboratory nanoamp current comparison with sub-part-per-million uncertainty. https://doi.org/10.1109/tim.2018.2879126

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