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Progress towards comparison of quantum and classical vacuum standards



Daniel Barker, Nikolai Klimov, Eite Tiesinga, James A. Fedchak, Julia Scherschligt, Stephen Eckel


We present our progress towards a comparison of NIST's cold atom primary vacuum standard and a dynamic expansion vacuum standard. The cold atom vacuum standard (CAVS) converts the loss rate of atoms from a magnetic trap to a vacuum pressure using ab initio calculations of the quantum atom-molecule collision cross-section. To validate the CAVS, we have constructed a new flowmeter and dynamic expansion system that can produce low-uncertainty pressures in the ultra-high-vacuum range that is required for atom trapping. We discuss the operation and systematics of both the CAVS and flowmeter.
Proceedings Title
Measurement: Sensors
Conference Dates
August 30-September 3, 2021
Conference Location
Yokohama, JP
Conference Title
XXIII World Congress of the International Measurement Confederation (IMEKO2021)


vacuum metrology, laser cooling, atom-molecule scattering


Barker, D. , Klimov, N. , Tiesinga, E. , Fedchak, J. , Scherschligt, J. and Eckel, S. (2021), Progress towards comparison of quantum and classical vacuum standards, Measurement: Sensors, Yokohama, JP, [online],, (Accessed June 19, 2024)


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Created September 22, 2021, Updated November 29, 2022