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Youssef S Hassan (Assoc)

Youssef is a graduate student in the Neutral Atom Optical Clock group. He works on developing Yb optical lattice clocks (OLCs) for next generation quantum time metrology. His focus has been on suppressing black-body radiation shift, the largest source of uncertainty in OLCs. He has also been involved in efforts to cool clock atoms to sub-uK for better characterization of lattice induced light clock shifts, and in introducing techniques to control the spatial atomic distribution inside the lattice. Youssef graduated with B.Sc. in Physics from the University of Science and Technology at Zewail City, Egypt in 2017.

Publications

Lattice Light Shift Evaluations In a Dual-Ensemble Yb Optical Lattice Clock

Author(s)
Tobias Bothwell, Roger Brown, Benjamin Hunt, Jacob Siegel, Tanner Grogan, Youssef Hassan, Kyle Beloy, Andrew Ludlow, Kurt Gibble, Takumi Kobayashi, Marianna Safronova, Sergey Porsev
In state-of-the-art optical lattice clocks, beyond-electric-dipole polarizability terms lead to a break-down of magic wavelength trapping. In this Letter, we

Ratchet Loading and Multi-Ensemble Operation in an Optical Lattice Clock

Author(s)
Youssef Hassan, Takumi Kobayashi, Tobias Bothwell, Jacob Siegel, Benjamin Hunt, Kyle Beloy, Kurt Gibble, Tanner Grogan, Andrew Ludlow
We demonstrate programmable control over the spatial distribution of ultra-cold atoms confined in an optical lattice. The control is facilitated through a

Clock-line-mediated Sisyphus Cooling

Author(s)
Jacob Siegel, Benjamin Hunt, Tanner Grogan, Youssef Hassan, Kyle Beloy, Roger Brown, Andrew Ludlow, Chun-Chia Chen, Kurt Gibble
We demonstrate sub-recoil Sisyphus cooling using the long-lived 3P0 clock state in alkaline-earthlike ytterbium. A 1388 -nm optical standing wave nearly

Improved interspecies optical clock comparisons through differential spectroscopy

Author(s)
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
Created May 23, 2018, Updated January 22, 2024