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David Hume (Fed)


David Hume is a staff physicist in the Ion Storage Group. His projects aim at developing and improving optical clocks using quantum metrology techniques. Notably, quantum-logic spectroscopy allows for precision measurement of a broad array trapped-ion species that cannot be directly laser cooled or detected. His group operates optical clocks based on quantum logic spectroscopy of aluminum ions and uses them for applications ranging from frequency standards to fundamental physics.


NIST Bronze Medal, Precision Molecular Spectroscopy, 2021

NIST Gold Medal, Optical Clock Network, 2019

Humboldt Research Fellowship, 2012

National Research Council Fellowship, 2011


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

Scalable Quantum Logic Spectroscopy

Kaifeng Cui, Jose Valencia, Kevin Boyce, Ethan Clements, David Leibrandt, David Hume
In quantum logic spectroscopy (QLS), one species of trapped ion is used as a sensor to detect the state of an otherwise inaccessible ion species. This extends

Patents (2018-Present)

Spherical Ion Trap and Trapping Ions

NIST Inventors
Jeffrey Sherman , David Hume , Roger Brown and David Leibrandt
A spherical ion trap includes a substrate and an ion aperture; two RF electrodes in electrostatic communication with an ion trapping region; RF ground electrodes in electrostatic communication with the ion trapping region; and the ion trapping region bounded by opposing RF electrodes and the RF
Created October 23, 2018, Updated December 8, 2022