Towards an optical lattice clock based on neutral mercury

We are investigating the possibilities of using neutral mercury as a new species to realize a highly accurate atomic clock using the non-perturbing dipole lattice trapping scheme. Typically, accuracy below 10-17 is targeted, which would make neutral mercury an interesting candidate for a redefinition of the SI second. This paper presents our on-going work towards the realization of an optical lattice clock using neutral mercury. We will describe a 254 nm laser source delivering several hundreds of milliWatts at this wavelength with a suitably low frequency noise for laser cooling and magneto-optic trapping. We will describe our vacuum system for magneto-optic trap and report on the status of our work regarding magneto-optic trapping of mercury. We will also describe our clock laser at 266 nm.Institut Francilien de Recherche sur les Atomes Froids (IFRAF)Centre National d'Études Spatiales (CNES

Atomic frequency standards and the time measurement

International audienceNot Availabl

Atomic frequency standards and the time measurement

International audienceNot Availabl

Testing the Stability of Fundamental Constants Using Atomic Fountains

International audienceWe report a test of the stability of fundamental constants based on laboratory experiments. This test relies on high-precision comparisons of atomic frequencies. The ground state hyperfine frequencies of 87Rb and 133Cs are compared over five years using atomic fountains. These measurements lead to the following constraint {d / {dt}} ln ( {(g{C} {s} /g{Rb} )alpha 0.44 } ; ) = (0.2 ± 7.0) × 10{ - 16} {yr}{ - 1} (1sigma uncertainty) where g is the nuclear g-factor and alpha the fine structure constant