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Daniel Barker (Fed)

Daniel Barker is a physicist in the Thermodynamic Metrology Group in the Sensor Science Division. He received a B.A. in Physics from Goucher College and a Ph.D. in atomic, molecular, and optical physics from the University of Maryland, where he studied quantum degenerate gases of alkaline-earth elements. Daniel came to NIST as a National Research Council Postdoctoral Research Associate to develop primary vacuum sensors under the Cold Core Technology program. Since joining the NIST staff, his research has focused on developing chip-scale sensors based on laser-cooled atoms or optomechanical systems, particularly for temperature and pressure metrology.

Research Projects

Cold Core Technology Platform

Photonic Thermometry


A Primary Standard for Measuring Vacuum

Bringing Atoms to a Standstill: NIST Miniaturizes Laser Cooling

A New Way to Measure Nearly Nothing


Precise Quantum Measurement of Vacuum with Cold Atoms

Daniel Barker, Bishnu Acharya, James A. Fedchak, Nikolai Klimov, Eric Norrgard, Julia Scherschligt, Eite Tiesinga, Stephen Eckel
We describe the cold-atom vacuum standards (CAVS) under development at the National Institute of Standards and Technology. The CAVS measures pressure in the

A constant pressure flowmeter for the extremely high vacuum

Stephen Eckel, Daniel Barker, James A. Fedchak, Emmanuel Newsome, Julia Scherschligt, Robert E. Vest
We demonstrate operation of a constant-pressure flowmeter capable of generating and accurately measuring flows as low as $1\times10^-13}$mol/s. Generation of

Comparison of two multiplexed portable cold atom vacuum standards

Lucas Ehinger, Bishnu Acharya, Daniel Barker, James A. Fedchak, Julia Scherschligt, Eite Tiesinga, Stephen Eckel
We compare the vacuum measured by two portable cold atom vacuum standards (pCAVS) based on ultracold $^7$Li atoms. Our pCAVS devices share the same laser system

Laser Spectroscopy of the y7PJo states of Cr I

Eric Norrgard, Daniel Barker, Stephen Eckel, Sergey Porsev, Charles Cheung, Mikhail Kozlov, Ilya Tupitsyn, Marianna Safronova
Here we report measured and calculated values of decay rates of the 3d$^4$($^5$D)4s4p($^3$P$^\rmo}}$)\ y$^7$P$^\rmo}}_2,3,4}$ states of Cr I. The decay rates

Patents (2018-Present)

Created July 30, 2019, Updated December 27, 2022