162 citations · 1.1k across the 21 of their papers we have counts for
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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…
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…
Uncertainty evaluation of an Yb optical lattice clock at NMIJ
Takumi Kobayashi, Daisuke Akamatsu, Yusuke Hisai +6
We report an uncertainty evaluation of an Yb optical lattice clock with a total fractional uncertainty of , which is mainly limited by the lattice-induce…
A frequency-stabilized light source at 399 nm using an Yb hollow-cathode lamp
Takehiko Tanabe, Daisuke Akamatsu, Hajime Inaba +5
We demonstrate a diode laser system operating at 399 nm that is stabilized to the electric dipole transition in ytterbium (Yb) atoms in…
Absolute frequency measurements and hyperfine structures of the molecular iodine transitions at 578 nm
Takumi Kobayashi, Daisuke Akamatsu, Kazumoto Hosaka +6
We report absolute frequency measurements of 81 hyperfine components of the rovibrational transitions of molecular iodine at 578 nm using the second harmonic generation of an 1156-…