303 citations · 1.7k across the 27 of their papers we have counts for
27 papers
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}…
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…
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…
Low-energy scattering of ultracold atoms by a dielectric nanosphere
T. Yamaguchi, D. Akamatsu, R. Kanamoto
We theoretically study the low-energy scattering of ultracold atoms by a dielectric nanosphere of silica glass levitated in a vacuum. The atom and dielectric surface interact via d…
Demonstration of the nearly continuous operation of an Yb optical lattice clock for half a year
Takumi Kobayashi, Daisuke Akamatsu, Kazumoto Hosaka +6
Optical lattice clocks surpass primary Cs microwave clocks in frequency stability and accuracy, and are promising candidates for a redefinition of the second in the International S…
Improved Frequency Ratio Measurement with 87Sr and 171Yb Optical Lattice Clocks at NMIJ
Yusuke Hisai, Daisuke Akamatsu, Takumi Kobayashi +4
We report improved frequency ratio measurement with Sr and Yb optical lattice clocks at the National Metrology Institute of Japan (NMIJ). The Sr optical latti…