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Julia K. Scherschligt, James A. Fedchak, Zeeshan Ahmed, Daniel S. Barker, Kevin O. Douglass, Stephen P. Eckel, Edward T. Hanson, Jay H. Hendricks, Thomas P. Purdy, Jacob E. Ricker, Robinjeet Singh
Abstract
The measurement science in realizing and disseminating the SI unit for pressure, the pascal (Pa), has been the subject of much interest at NIST. Modern optical-based techniques for pascal metrology have been investigated, including multi-photon ionization and cavity ringdown spectroscopy. Work is ongoing to recast the pascal in terms of quantum properties and fundamental constants and in so doing, make vacuum metrology consistent with the global trend toward quantum-based metrology. NIST has ongoing projects that interrogate the index of refraction of a gas using an optical cavity for low vacuum, and count background particles in high vacuum to extreme high vacuum using trapped laser-cooled atoms.
Scherschligt, J.
, Fedchak, J.
, Ahmed, Z.
, Barker, D.
, Douglass, K.
, Eckel, S.
, Hanson, E.
, Hendricks, J.
, Purdy, T.
, Ricker, J.
and Singh, R.
(2018),
Quantum-based vacuum metrology at NIST, Journal of Vacuum Science & Technology A, [online], https://doi.org/10.1116/1.5033568
(Accessed October 10, 2025)