Related papers: Systematic evaluation of an atomic clock at 2e-18 …

As optical clocks are improved to reach the frequency uncertainty below the 10$^{-17}$ level, the frequency shift due to the blackbody radiation (BBR) has been one of the major systematic effects hindering further improvement. To evaluate…

Existing optical lattice clocks demonstrate a high level of performance, but they remain complex experimental devices. In order to address a wider range of applications including those requiring transportable devices, it will be necessary…

We measured the absolute frequency of the $^1S_0$ - $^3P_0$ transition of $^{171}$Yb atoms confined in a one-dimensional optical lattice relative to the SI second. The determined frequency was 518 295 836 590 863.38(57) Hz. The uncertainty…

Active optical frequency standards provide interesting alternatives to their passive counterparts. Particularly, such a clock alone continuously generates highly-stable narrow-line laser radiation. Thus a local oscillator is not required to…

We describe a transportable optical lattice clock based on the $^1\mathrm{S}_0 \rightarrow {^3\mathrm{P}_0}$ transition of lattice-trapped $^{87}$Sr atoms with a total systematic uncertainty of $2.1 \times 10^{-18}$. The blackbody radiation…

We describe the Sr optical lattice clock apparatus at NPL with particular emphasis on techniques used to increase reliability and minimise the human requirement in its operation. Central to this is a clock-referenced transfer cavity scheme…

Atomic lattice clocks have spurred numerous ideas for tests of fundamental physics, detection of general relativistic effects, and studies of interacting many-body systems. On the other hand, molecular structure and dynamics offer rich…

Laboratory optical atomic clocks achieve remarkable accuracy (now counted to 18 digits or more), opening possibilities to explore fundamental physics and enable new measurements. However, their size and use of bulk components prevent them…

We discuss the minimization of the Dick effect in an optical lattice clock. We show that optimizing the time sequence of operation of the clock can lead to a significant reduction of the clock stability degradation by the frequency noise of…

Optical atomic clocks with unrivaled precision and accuracy have advanced the frontier of precision measurement science and opened new avenues for exploring fundamental physics. A fundamental limitation on clock precision is the Standard…

Atomic clocks occupy a unique position in measurement science, exhibiting higher accuracy than any other measurement standard and underpinning six out of seven base units in the SI system. By exploiting higher resonance frequencies, optical…

The experimental comparison of two thulium optical lattice clocks in a time interval of up to one hour has been carried out. The synchronous comparison of a clock transition in two independent atomic ensembles using a single ultrastable…

Optical clocks are not only powerful tools for prime fundamental research, but are also deemed for the re-definition of the SI base unit second as they now surpass the performance of caesium atomic clocks in both accuracy and stability by…

This letter presents the principles and techniques of active optical clock, a special laser combining the laser physics of one-atom laser, bad-cavity gas laser, super-cavity stabilized laser and optical atomic clock. As an example, a…

Despite being a canonical example of quantum mechanical perturbation theory, as well as one of the earliest observed spectroscopic shifts, the Stark effect contributes the largest source of uncertainty in a modern optical atomic clock…

We describe a frequency stabilized diode laser at 698 nm used for high resolution spectroscopy of the 1S0-3P0 strontium clock transition. For the laser stabilization we use state-of-the-art symmetrically suspended optical cavities optimized…

We have investigated the benefits of spin squeezed states for clocks operated with typical Brownian frequency noise-limited laser sources. Based on an analytic model of the closed servo-loop of an optical atomic clock, we can give…

We propose a new frequency standard based on a $4f^{14} 6s6p~ ^3\!P_0 - 4f^{13} 6s^2 5d ~(J=2)$ transition in neutral Yb. This transition has a potential for high stability and accuracy and the advantage of the highest sensitivity among…

With 87-Sr atoms confined in a one dimensional optical lattice, the frequency of the optical clock transition 5s^2 ^1S_0 - 5s5p ^3P_0 has been determined to be 429 228 004 229 872.9(5) Hz. The transition frequency was measured with the help…

The preparation of large, low-entropy, highly coherent ensembles of identical quantum systems is foundational for many studies in quantum metrology, simulation, and information. Here, we realize these features by leveraging the favorable…