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Andrew Ludlow (Fed)

Andrew Ludlow is a physicist and leader of the Neutral Atom Optical Clock Group in the Physical Measurement Laboratory at the National Institute of Standards and Technology in Boulder. He is also a lecturer and adjoint professor at the University of Colorado Boulder, and a senior investigator in Q-SEnSE. His main research interests include the development of optical atomic clocks, cold atom systems for quantum metrology, ultrastable optical sources and laser interferometry, and the application of these systems to fundamental physics studies and advanced technology. He received a Ph.D. in Physics from the University of Colorado Boulder in 2008 and a B.S. in Physics from Brigham Young University in 2002. Andrew is a Fellow of the American Physical Society, and is the recipient of various awards for his research activity including the APS Pipkin Award, the Arthur S. Flemming Award, the Presidential Early Career Award, the EFTF Young Scientist Award, and the APS DAMOP Thesis Prize.


Improved interspecies optical clock comparisons through differential spectroscopy

May E. Kim, Will McGrew, Nicholas Nardelli, Ethan Clements, Youssef Hassan, Xiaogang Zhang, Jose Valencia, Holly Leopardi, David Hume, Tara Fortier, Andrew Ludlow, David Leibrandt
Comparisons of high-accuracy optical atomic clocks \citeLudlow2015} are essential for precision tests of fundamental physics \citeSafronova2018}, relativistic

Optical Atomic Clock aboard an Earth-orbiting Space Station (OACESS): Enhancing searches for physics beyond the standard model in space

Vladimir Schkolnik, Dmitry Budker, Oliver Farttman, Victor Flambaum, Leo Hollberg, Tigran Kalaydzhyan, Shimon Kolkowitz, Markus Krutzik, Andrew Ludlow, Nathan R. Newbury, Christopher Pyrlik, Laura Sinclair, Yevgeny Stadnik, Ingmari Tietje, Jun Ye, Jason Williams
We present a concept for a high-precision optical atomic clock (OAC) operating on an Earth-orbiting space station. This pathfinder science mission will compare

Frequency Ratio Measurements with 18-Digit Accuracy Using a Network of Optical Clocks

Kyle Beloy, Martha I. Bodine, Tobias B. Bothwell, Samuel M. Brewer, Sarah L. Bromley, Jwo-Sy Chen, Jean-Daniel Deschenes, Scott Diddams, Robert J. Fasano, Tara Fortier, Youssef Hassan, David Hume, Dhruv Kedar, Colin J. Kennedy, Isaac Kader, Amanda Koepke, David Leibrandt, Holly Leopardi, Andrew Ludlow, Will McGrew, William Milner, Daniele Nicolodi, Eric Oelker, Tom Parker, John M. Robinson, Stefania Romisch, Stefan A. Schaeffer, Jeffrey Sherman, Laura Sinclair, Lindsay I. Sonderhouse, William C. Swann, Jian Yao, Jun Ye, Xiaogang Zhang
Atomic clocks occupy a unique position in measurement science, exhibiting higher accuracy than any other measurement standard and underpinning six out of seven

Patents (2018-Present)

Optical Reference Cavity

NIST Inventors
Franklyn Quinlan , Scott Diddams and Andrew Ludlow
An optical reference cavity includes: a cell that includes: a cylindrical body; end faces; an optical canal having an interior cylindrical geometry; and an exterior surface having an exterior cylindrical geometry; mirrors disposed on the end faces; an aspect ratio that is less than 1; a compression
Created May 31, 2018, Updated May 15, 2023