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arXiv · 2204.03705

Comparison of two multiplexed portable cold-atom vacuum standards

Lucas H. Ehinger·Bishnu P. Acharya·Daniel S. Barker·James A. Fedchak·Julia Scherschligt·Eite Tiesinga·Stephen Eckel
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Abstract

We compare the vacuum measured by two portable cold-atom vacuum standards (pCAVS) based on ultracold $^7$Li atoms. The pCAVS are quantum-based standards that use a priori scattering calculations to convert a measured loss rate of cold atoms from a conservative trap into a background gas pressure. Our pCAVS devices share the same laser system and measure the vacuum concurrently. The two pCAVS together detected a leak with a rate on the order of $10^{-6}$ Pa L/s. After fixing the leak, the pCAVS measured a pressure of about 40 nPa with 2.6 % uncertainty. The two pCAVS agree within their uncertainties, even when swapping some of their component parts. Operation of the pCAVS was found to cause some additional outgassing, on the order of $10^{-8}$ Pa L/s, which can be mitigated in the future by better thermal management.

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Lucas H. Ehinger, Bishnu P. Acharya, Daniel S. Barker, James A. Fedchak, Julia Scherschligt, Eite Tiesinga, Stephen Eckel. 2022-04-07. Comparison of two multiplexed portable cold-atom vacuum standards. https://doi.org/10.1116/5.0095011

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