68 citations · 128 across the 10 of their papers we have counts for
10 papers
Cryogenic Optical Lattice Clock with Blackbody Radiation Stark Uncertainty
Youssef S. Hassan, Kyle Beloy, Jacob L. Siegel +9
Controlling the Stark perturbation from ambient thermal radiation is key to advancing the performance of many atomic frequency standards, including state-of-the-art optical lattice…
Coordinated international comparisons between optical clocks connected via fiber and satellite links
Thomas Lindvall, Marco Pizzocaro, Rachel M. Godun +62
Optical clocks provide ultra-precise frequency references that are vital for international metrology as well as for tests of fundamental physics. To investigate the level of agreem…
Improved absolute frequency measurement of Yb at NMIJ with uncertainty below
Takumi Kobayashi, Akiko Nishiyama, Kazumoto Hosaka +6
We report improved absolute frequency measurement of the SP transition of Yb at National Metrology Institute of Japan (NMIJ) by comparing the $^{171}…
Measurement of transition frequencies and hyperfine constants of molecular iodine at 520.2 nm
Akiko Nishiyama, Sho Okubo, Takumi Kobayashi +2
We measured the transition frequencies of the hyperfine components in the four lines (P(34) 39-0, R(36) 39-0, P(33) 39-0, and R(35) 39-0) of the B-X transitions of molecular iodine…
Lattice Light Shift Evaluations In a Dual-Ensemble Yb Optical Lattice Clock
Tobias Bothwell, Benjamin D. Hunt, Jacob L. Siegel +9
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 report a novel approac…
Ratchet Loading and Multi-Ensemble Operation in an Optical Lattice Clock
Youssef S. Hassan, Takumi Kobayashi, Tobias Bothwell +6
We demonstrate programmable control over the spatial distribution of ultra-cold atoms confined in an optical lattice. The control is facilitated through a combination of spatial ma…
Generation of a precise time scale assisted by a near-continuously operating optical lattice clock
Takumi Kobayashi, Daisuke Akamatsu, Kazumoto Hosaka +8
We report on a reduced time variation of a time scale with respect to Coordinated Universal Time (UTC) by steering a hydrogen-maser-based time scale with a near-continuously operat…
Isotope-shift analysis with the transition in ytterbium
Akio Kawasaki, Takumi Kobayashi, Akiko Nishiyama +2
Measurements of isotope shifts have recently been attracting considerable attention due to their potentials in searching for new forces. We report on the isotope shifts of the $4f^…
Observation of the clock transition at 431 nm in Yb
Akio Kawasaki, Takumi Kobayashi, Akiko Nishiyama +2
We report on the observation of the transition at 431 nm in Yb by depleting atoms in a magneto-optical trap formed by the $6s^{2…
Search for ultralight dark matter from long-term frequency comparisons of optical and microwave atomic clocks
Takumi Kobayashi, Akifumi Takamizawa, Daisuke Akamatsu +8
We search for ultralight scalar dark matter candidates that induce oscillations of the fine structure constant, the electron and quark masses, and the quantum chromodynamics energy…