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Frequency ratio of Yb and Sr clocks with 5 × 10−17 uncertainty at 150 seconds averaging time

Nature Photonics volume 10, pages 258–261 (2016)Cite this article

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Abstract

Transition frequencies of atoms and ions are among the most accurately accessible quantities in nature, playing important roles in pushing the frontiers of science by testing fundamental laws of physics, in addition to a wide range of applications such as satellite navigation systems. Atomic clocks based on optical transitions approach uncertainties of 10−18 (refs 1–3), where full frequency descriptions are far beyond the reach of the SI second. Direct measurements of the frequency ratios of such super clocks, on the other hand, are not subject to this limitation4,5,6,7,8. They can verify consistency and overall accuracy for an ensemble of super clocks, an essential step towards a redefinition of the second9. Here we report a measurement that finds the frequency ratio of neutral ytterbium and strontium clocks to be ℛ = 1.207507039343337749(55), with a fractional uncertainty of 4.6 × 10−17 and a measurement instability as low as 4 × 10−16 (τ/s)−1/2.

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Figure 1: Experimental set-up for Yb/Sr ratio measurements.
Figure 2: Ratio measurement stability.
Figure 3: History of ratio measurements.

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Change history

  • 15 March 2016

    In the version of this Letter originally published online, in Table 2, the column heading '171Yb' was mistakenly included. This has now been corrected in all versions of the Letter.

References

  1. Chou, C. W., Hume, D. B., Koelemeij, J. C. J., Wineland, D. J. & Rosenband, T. Frequency comparison of two high-accuracy Al+ optical clocks. Phys. Rev. Lett. 104, 070802 (2010).

    Article  ADS  Google Scholar 

  2. Ushijima, I., Takamoto, M., Das, M., Ohkubo, T. & Katori, H. Cryogenic optical lattice clocks. Nature Photon. 9, 185–189 (2015).

    Article  ADS  Google Scholar 

  3. Nicholson, T. L. et al. Systematic evaluation of an atomic clock at 2 × 10−18 total uncertainty. Nature Commun. 6, 6896 (2015).

    Article  ADS  Google Scholar 

  4. Rosenband, T. et al. Frequency ratio of Al+ and Hg+ single-ion optical clocks; metrology at the 17th decimal place. Science 319, 1808–1812 (2008).

    Article  ADS  Google Scholar 

  5. Matsubara, K. et al. Direct comparison of a Ca+ single-ion clock against a Sr lattice clock to verify the absolute frequency measurement. Opt. Express 20, 22034–22041 (2012).

    Article  ADS  Google Scholar 

  6. Godun, R. M. et al. Frequency ratio of two optical clock transitions in 171Yb+ and constraints on the time variation of fundamental constants. Phys. Rev. Lett. 113, 210801 (2014).

    Article  ADS  Google Scholar 

  7. Akamatsu, D. et al. Frequency ratio measurement of 171Yb and 87Sr optical lattice clocks. Opt. Express 22, 7898–7905 (2014).

    Article  ADS  Google Scholar 

  8. Yamanaka, K., Ohmae, N., Ushijima, I., Takamoto, M. & Katori, H. Frequency ratio of 199Hg and 87Sr optical lattice clocks beyond the SI limit. Phys. Rev. Lett. 114, 230801 (2015).

    Article  ADS  Google Scholar 

  9. Riehle, F. Towards a redefinition of the second based on optical atomic clocks. C. R. Phys. 16, 506–515 (2015).

    Article  Google Scholar 

  10. Katori, H., Takamoto, M., Pal'chikov, V. G. & Ovsiannikov, V. D. Ultrastable optical clock with neutral atoms in an engineered light shift trap. Phys. Rev. Lett. 91, 173005 (2003).

    Article  ADS  Google Scholar 

  11. Van Tilburg, K., Leefer, N., Bougas, L. & Budker, D. Search for ultralight scalar dark matter with atomic spectroscopy. Phys. Rev. Lett. 115, 011802 (2015).

    Article  ADS  Google Scholar 

  12. Derevianko, A. & Pospelov, M. Hunting for topological dark matter with atomic clocks. Nature Phys. 10, 933–936 (2014).

    Article  ADS  Google Scholar 

  13. Schive, H., Chiueh, T. & Broadhurst, T. Cosmic structure as the quantum interference of a coherent dark wave. Nature Phys. 10, 496–499 (2014).

    Article  ADS  Google Scholar 

  14. Itano, W. M. et al. Quantum projection noise: population fluctuations in two-level systems. Phys. Rev. A 47, 3554–3570 (1993).

    Article  ADS  Google Scholar 

  15. Häfner, S. et al. 8 × 10−17 fractional laser frequency instability with a long room-temperature cavity. Opt. Lett. 40, 2112–2115 (2015).

    Article  ADS  Google Scholar 

  16. Dick, G. J. Local oscillator induced instabilities in trapped ion frequency standards. In Proc. 19th Precise Time Time Interval Meet. (ed. Sydnor, R. L.) 133–147 (US Naval Observatory/Goddard Space Flight Center, 1988).

    Google Scholar 

  17. Bize, S., Sortais, Y. & Lemonde, P. Interrogation oscillator noise rejection in the comparison of atomic fountains. IEEE Trans. Ultrason. Ferroelectr. Freq. Control 47, 1253–1255 (2000).

    Article  Google Scholar 

  18. Takamoto, M., Takano, T. & Katori, H. Frequency comparison of optical lattice clocks beyond the Dick limit. Nature Photon. 5, 288–292 (2011).

    Article  ADS  Google Scholar 

  19. Chou, C. W., Hume, D. B., Thorpe, M. J., Wineland, D. J. & Rosenband, T. Quantum coherence between two atoms beyond Q = 1015. Phys. Rev. Lett. 106, 160801 (2011).

    Article  ADS  Google Scholar 

  20. Middelmann, T., Falke, S., Lisdat, C. & Sterr, U. High accuracy correction of blackbody radiation shift in an optical lattice clock. Phys. Rev. Lett. 109, 263004 (2012).

    Article  ADS  Google Scholar 

  21. Bloom, B. J. et al. An optical lattice clock with accuracy and stability at the 10−18 level. Nature 506, 71–75 (2014).

    Article  ADS  Google Scholar 

  22. Beloy, K. et al. Atomic clock with 1 × 10−18 room-temperature blackbody Stark uncertainty. Phys. Rev. Lett. 113, 260801 (2014).

    Article  ADS  Google Scholar 

  23. Barber, Z. W. et al. Optical lattice induced light shifts in an Yb atomic clock. Phys. Rev. Lett. 100, 103002 (2008).

    Article  ADS  Google Scholar 

  24. Katori, H., Ovsiannikov, V. D., Marmo, S. I. & Palchikov, V. G. Strategies for reducing the light shift in atomic clocks. Phys. Rev. A 91, 052503 (2015).

    Article  ADS  Google Scholar 

  25. Inaba, H. et al. Spectroscopy of 171Yb in an optical lattice based on laser linewidth transfer using a narrow linewidth frequency comb. Opt. Express 21, 7891–7896 (2013).

    Article  ADS  Google Scholar 

  26. Hinkley, N. et al. An atomic clock with 10−18 instability. Science 341, 1215–1218 (2013).

    Article  ADS  Google Scholar 

  27. Takamoto, M. et al. Frequency ratios of Sr, Yb, and Hg based optical lattice clocks and their applications. C. R. Phys. 16, 489–498 (2015).

    Article  Google Scholar 

  28. Recommended Values of Standard Frequencies (BIPM, 2013); http://www.bipm.org/en/publications/mises-en-pratique/standard-frequencies.html.

  29. Greenhall, C. A., Howe, D. A. & Percival, D. B. Total variance, an estimator of long-term frequency stability. IEEE Trans. Ultrason. Ferroelectr. Freq. Control 46, 1183–1191 (1999).

    Article  Google Scholar 

  30. Le Targat, R. et al. Experimental realization of an optical second with strontium lattice clocks. Nature Commun. 4, 2109 (2013).

    Article  ADS  Google Scholar 

  31. Ma, L.-S., Jungner, P., Ye, J. & Hall, J. L. Delivering the same optical frequency at two places: accurate cancellation of phase noise introduced by an optical fiber or other time-varying path. Opt. Lett. 19, 1777–1779 (1994).

    Article  ADS  Google Scholar 

  32. Takamoto, M. et al. Improved frequency measurement of a one-dimensional optical lattice clock with a spin-polarized fermionic 87Sr isotope. J. Phys. Soc. Jpn 75, 104302 (2006).

    Article  ADS  Google Scholar 

  33. Angstmann, E. J., Dzuba, V. A. & Flambaum, V. V. Relativistic effects in two valence-electron atoms and ions and the search for variation of the fine-structure constant. Phys. Rev. A 70, 014102 (2004).

    Article  ADS  Google Scholar 

  34. Lea, S. N. Limits to time variation of fundamental constants from comparisons of atomic frequency standards. Eur. Phys. J. Special Topics 163, 37–53 (2008).

    Article  ADS  Google Scholar 

  35. Huntemann, N. et al. Improved limit on a temporal variation of m p /m e from comparisons of Yb+ and Cs atomic clocks. Phys. Rev. Lett. 113, 210802 (2014).

    Article  ADS  Google Scholar 

  36. Uzan, J.-P. The fundamental constants and their variation: observational and theoretical status. Rev. Mod. Phys. 75, 403–455 (2003).

    Article  ADS  MathSciNet  Google Scholar 

  37. Arvanitaki, A., Huang, J. & Van Tilburg, K. Searching for dilaton dark matter with atomic clocks. Phys. Rev. D 91, 015015 (2015).

    Article  ADS  Google Scholar 

  38. Falke, S. et al. A strontium lattice clock with 3 × 10−17 inaccuracy and its frequency. New J. Phys. 16, 073023 (2014).

    Article  ADS  Google Scholar 

  39. Santarelli, G. et al. Frequency stability degradation of an oscillator slaved to a periodically interrogated atomic resonator. IEEE Trans. Ultrason. Ferroelectr. Freq. Contr. 45, 887–894 (1998).

    Article  Google Scholar 

  40. Lemke, N. D. et al. Spin-1/2 optical lattice clock. Phys. Rev. Lett. 103, 063001 (2009).

    Article  ADS  Google Scholar 

  41. Sherman, J. A. et al. High-accuracy measurement of atomic polarizability in an optical lattice clock. Phys. Rev. Lett. 108, 153002 (2012).

    Article  ADS  Google Scholar 

  42. Blatt, S. et al. Rabi spectroscopy and excitation inhomogeneity in a one-dimensional optical lattice clock. Phys. Rev. A 80, 052703 (2009).

    Article  ADS  Google Scholar 

  43. Ovsiannikov, V. D., Pal'chikov, V. G., Taichenachev, A. V., Yudin, V. I. & Katori, H. Multipole, nonlinear, and anharmonic uncertainties of Sr atoms in an optical lattice. Phys. Rev. A 88, 013405 (2013).

    Article  ADS  Google Scholar 

  44. Lemke, N. D. et al. p-wave cold collisions in an optical lattice clock. Phys. Rev. Lett. 107, 103902 (2011).

    Article  ADS  Google Scholar 

  45. Falke, S., Misera, M., Sterr, U. & Lisdat, C. Delivering pulsed and phase stable light to atoms of an optical clock. Appl. Phys. B 107, 301–311 (2012).

    Article  ADS  Google Scholar 

  46. Iwakuni, K. et al. Narrow linewidth comb realized with a mode-locked fiber laser using an intra-cavity waveguide electro-optic modulator for high-speed control. Opt. Express 20, 13769–13776 (2012).

    Article  ADS  Google Scholar 

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Acknowledgements

We thank H. Inaba and F.-L. Hong of AIST/NMIJ for providing the frequency comb. We thank T. Pruttivarasin for commenting on the manuscript. This work received partial support from the Japan Society for the Promotion of Science (JSPS) through its Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST) and from the Photon Frontier Network Program of the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan. N.N. acknowledges RIKEN's Foreign Postdoctoral Researcher (FPR) program for financial support.

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Authors and Affiliations

  1. Quantum Metrology Laboratory, RIKEN, Wako, 351-0198, Saitama, Japan

    Nils Nemitz, Takuya Ohkubo, Masao Takamoto, Ichiro Ushijima, Manoj Das, Noriaki Ohmae & Hidetoshi Katori

  2. Innovative Space-Time Project, ERATO, Japan Science and Technology Agency, Bunkyo-ku, Tokyo, 113-8656, Japan

    Takuya Ohkubo, Masao Takamoto, Ichiro Ushijima, Manoj Das, Noriaki Ohmae & Hidetoshi Katori

  3. Department of Applied Physics, Graduate School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8656, Japan

    Takuya Ohkubo, Noriaki Ohmae & Hidetoshi Katori

  4. RIKEN Center for Advanced Photonics, Wako, 351-0198, Saitama, Japan

    Masao Takamoto, Ichiro Ushijima, Manoj Das & Hidetoshi Katori

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  1. Nils Nemitz
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Contributions

H.K. initiated and coordinated the experiments. M.T. and I.U. characterized and operated the Sr clock, N.N. and T.O. the Yb clock. N.O. maintained and operated the frequency comb. All authors contributed to the experimental set-ups, discussed the results and commented on the manuscript.

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Correspondence to Hidetoshi Katori.

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Nemitz, N., Ohkubo, T., Takamoto, M. et al. Frequency ratio of Yb and Sr clocks with 5 × 10−17 uncertainty at 150 seconds averaging time. Nature Photon 10, 258–261 (2016). https://doi.org/10.1038/nphoton.2016.20

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