162 citations · 707 across the 16 of their papers we have counts for
16 papers
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…
Dual-Mode Operation of an Optical Lattice Clock Using Strontium and Ytterbium Atoms
Daisuke Akamatsu, Takumi Kobayashi, Yusuke Hisai +4
We have developed an optical lattice clock that can operate in dual modes: a strontium (Sr) clock mode and an ytterbium (Yb) clock mode. Dual-mode operation of the Sr-Yb optical la…
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…