Optical atomic clocks

@article{Poli2013OpticalAC,
  title={Optical atomic clocks},
  author={Nicola Poli and Christopher W. Oates and Patrick Gill and Guglielmo Maria Tino},
  journal={Rivista Del Nuovo Cimento},
  year={2013},
  volume={36},
  pages={555-624}
}
In the last ten years extraordinary results in time and frequency metrology have been demonstrated. Frequency-stabilization techniques for continuous-wave lasers and femto-second optical frequency combs have enabled a rapid development of frequency standards based on optical transitions in ultra-cold neutral atoms and trapped ions. As a result, today's best performing atomic clocks tick at an optical rate and allow scientists to perform high-resolution measurements with a precision approaching… 
Optical Atomic Clocks for Redefining SI Units of Time and Frequency
Nowadays, most of the standards of measurement are based on fundamental constants, and among all, the SI units of time and frequency are realized with the highest precision. The SI unit of time
Towards a transportable aluminium ion quantum logic optical clock.
TLDR
A transportable optical clock based on a single trapped aluminum ion, which is interrogated via quantum logic spectroscopy, is developed, employing singly charged calcium as the logic ion for sympathetic cooling, state preparation, and readout.
General Methods for Suppressing the Light Shift in Atomic Clocks Using Power Modulation
We show that the light shift in atomic clocks can be suppressed using time variation of the interrogation field intensity. By measuring the clock output at two intensity levels, error signals can be
In-orbit operation of an atomic clock based on laser-cooled 87Rb atoms
TLDR
The authors demonstrate the first in-orbit atomic clock using cold Rb atoms operating in microgravity and opening possibilities of space surveys and tests of fundamental physics.
Seconds-scale coherence on an optical clock transition in a tweezer array
TLDR
A platform that combines the key strengths of these two approaches, based on arrays of individual strontium atoms held within optical tweezers is demonstrated, establishing optical tweezer arrays as a powerful tool for coherent control of optical transitions for metrology and quantum information science.
Atomic clocks for geodesy
TLDR
This review of experimental progress on optical atomic clocks and frequency transfer is reviewed, and the prospects of using these technologies for geodetic measurements and for the modelling and understanding of the authors' Earth are considered.
Precision measurements with cold atoms and trapped ions
Recent progresses on quantum control of cold atoms and trapped ions in both the scientific and technological aspects greatly advance the applications in precision measurement. Thanks to the
Broadband lasers for photo-ionization and repumping of trapped ions
A frequency-stable, broadband laser is presented for experiments on trapped ions. Because the design is based on widely available semiconductor optical amplifier technology, similar lasers can be
Towards an optical clock for space: Compact, high-performance optical lattice clock based on bosonic atoms
Optical clocks operated on satellites are expected to open up new opportunities in time transfer, geodesy, fundamental physics, and satellite navigation. Here we demonstrate an important first step
Inner-shell clock transition in atomic thulium with a small blackbody radiation shift
TLDR
An unusually low sensitivity of a 1.14 μm inner-shell clock transition in neutral Tm atoms to BBR is demonstrated, which allows the development of lanthanide-based optical clocks with a relative uncertainty at the 10−17 level.
...
...

References

SHOWING 1-10 OF 21 REFERENCES
An optical lattice clock with accuracy and stability at the 10−18 level
TLDR
This work demonstrates a many-atom system that achieves an accuracy of 6.4 × 10−18, which is not only better than a single-ion-based clock, but also reduces the required measurement time by two orders of magnitude.
The space optical clocks project: Development of high-performance transportable and breadboard optical clocks and advanced subsystems
TLDR
The EU-FP7-SPACE-2010-1 project no. 263500 (SOC2) (2011–2015) aims at two “engineering confidence“, accurate transportable lattice optical clock demonstrators having relative frequency instability below 1×10−15 at 1 s integration time and relative inaccuracy below 5×10–17, which is about 2 and 1 orders better in instability and inaccuracy than today's best transportable clocks.
Prospects for frequency comparison of Sr and Hg optical lattice clocks toward 10−18 uncertainties
We are developing optical lattice clocks with a scope of attaining 10-18 fractional uncertainty. Cryogenic silicon cavity targeting 2×10-17 stability at 1s, will allow full utilization of the
Single-Ion Optical Frequency Standards and Measurement of their Absolute Optical Frequency
This work examines the current status of research on optical frequency standards based upon single trapped ions. Methods for the containment and laser cooling of such single-ion samples are briefly
Towards a magnesium optical lattice clock
  • S. Ruhmann, M. Riedmann, E. Rasel
  • Physics
    2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC)
  • 2011
Optical atomic clocks have large potential regarding accuracy and stability compared to the best microwave clocks. Alkaline-earth magnesium (Mg) is a promising candidate for a future neutral atom
Development of 171Yb optical lattice clock at KRISS
  • C. Park, D. Yu, J. Mun
  • Physics
    2012 Conference on Precision electromagnetic Measurements
  • 2012
We developed an <sup>171</sup>Yb optical lattice clock and measured the absolute frequency of the optical clock transition <sup>1</sup>S<sub>0</sub> (F = 1/2) - <sup>3</sup>P<sub>0</sub> (F = 1/2).
Blackbody effects in the Yb optical lattice clock
We report a high accuracy measurement of the differential static polarizability for the clock transition in a Yb lattice clock, a key parameter for determining the blackbody (BBR) shift of this
The quantum physics of atomic frequency standards
Basic physics of selected atomic systems: Hydrogen, alkali and other selected atoms. Transitions between atomic states. Ensemble of atoms: the density matrix. Electromagnetic and noise concepts:
A high stability optical frequency reference based on thermal calcium atoms
Here we report an imprecision below 10<sup>-14</sup> with a simple, compact optical frequency standard based upon thermal calcium atoms. Using a Ramsey-Bordé spectrometer we excite features with
Precision calculation of blackbody radiation shifts for metrology at the 18th decimal place
  • M. Safronova, M. Kozlov, C. Clark
  • Physics
    2011 Joint Conference of the IEEE International Frequency Control and the European Frequency and Time Forum (FCS) Proceedings
  • 2011
We developed a theoretical method within the framework of relativistic many-body theory to accurately treat correlation corrections in atoms with few valence electrons, and applied it to calculate
...
...