Bibliographies thématiques / Sr optical lattice clock

Littérature scientifique sur le sujet « Sr optical lattice clock »

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Publié le 14 mars 2023

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Articles de revues sur le sujet "Sr optical lattice clock"

Lin, Y., Q. Wang, Y. Li, F. Meng, B. Lin, E. Zang, Z. Sun, F. Fang, T. Li et Z. Fang. « The NIM Sr Optical Lattice Clock ». Journal of Physics : Conference Series 723 (juin 2016) : 012021. http://dx.doi.org/10.1088/1742-6596/723/1/012021.

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Hill, I. R., R. Hobson, W. Bowden, E. M. Bridge, S. Donnellan, E. A. Curtis et P. Gill. « A low maintenance Sr optical lattice clock ». Journal of Physics : Conference Series 723 (juin 2016) : 012019. http://dx.doi.org/10.1088/1742-6596/723/1/012019.

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Li, Ting, Tao Wang, Ye-Bing Wang, Ben-Quan Lu, Xiao-Tong Lu, Mo-Juan Yin et Hong Chang. « Experimental observation of quantum tunneling in shallow optical lattice ». Acta Physica Sinica 71, n^o 7 (2022) : 073701. http://dx.doi.org/10.7498/aps.71.20212038.

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For a one-dimensional optical lattice clock built in the horizontal direction, when the stability and uncertainty of the system reach the order of 10–18 or more, the clock frequency shift caused by the quantum tunneling effect becomes not negligible. In the shallow optical lattice, the quantum tunneling effect will cause the clock transition spectrum to be significantly broadened. So, in this paper the quantum tunneling phenomenon in the shallow optical lattice is studied, laying a foundation for the evaluation of uncertainty of 87Sr atomic optical lattice clock system. In this experiment, on the platform of one-dimensional 87Sr atomic optical lattice clock, the narrow-linewidth 1S0(<inline-formula><tex-math id="M4">\begin{document}$ \left|g \right\rangle $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="7-20212038_M4.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="7-20212038_M4.png"/></alternatives></inline-formula>)→3P0(<inline-formula><tex-math id="M5">\begin{document}$ \left|e \right\rangle $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="7-20212038_M5.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="7-20212038_M5.png"/></alternatives></inline-formula>) transition (that is, the clock transition) is excited by an ultra-stable and ultra-narrow linewidth 698 nm laser, and the distribution of strontium atoms in a specific quantum state is prepared. In the deep optical lattice, after the cold 87Sr atoms in preparation reach a <inline-formula><tex-math id="M6">\begin{document}$ \left|e,{n}_{z}=1 \right\rangle $\end{document}</tex-math><alternatives><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="7-20212038_M6.jpg"/><graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="7-20212038_M6.png"/></alternatives></inline-formula> state, the lattice depth of the optical lattice is adiabatically reduced. Then, the carrier-sideband resolved clock transition spectral line is detected in the shallow optical lattice. The obvious splitting of the carrier spectral line is observed from the clock transition spectral line, which indicates that the strontium atom has an obvious quantum tunneling phenomenon between the adjacent lattice sites of the optical lattice. In addition, when the lattice potential lattice depth is reduced, owing to the incommensurability of lattice light wavelength (813 nm) and clock laser wavelength (698 nm), the tunneling of atoms between adjacent lattice points will lead to spin-orbit coupling effect. Owing to the exceptionally long lifetime (120(3) s) of 3P0 state, it can not only suppress the decoherence, but also reduce the atomic loss rate caused by spontaneous emission. This has a natural advantage for studying the spin-orbit coupling of fermions. Therefore, the understanding of quantum tunneling mechanism in optical lattice is not only conducive to improving the uncertainty of the 87Sr atomic optical lattice clock, but also lays the foundation for observing the spin-orbit coupling effect of fermions on this platform.

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Wang, Qiang, Yi-Ge Lin, Ye Li, Bai-Ke Lin, Fei Meng, Er-Jun Zang, Tian-Chu Li et Zhan-Jun Fang. « Observation of Spin Polarized Clock Transition in 87 Sr Optical Lattice Clock ». Chinese Physics Letters 31, n^o 12 (décembre 2014) : 123201. http://dx.doi.org/10.1088/0256-307x/31/12/123201.

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Fouche, M., R. Le Targat, X. Baillard, A. Brusch, O. Tcherbakoff, G. D. Rovera et P. Lemonde. « Accuracy Evaluation of a $^{87}\hbox{Sr}$ Optical Lattice Clock ». IEEE Transactions on Instrumentation and Measurement 56, n^o 2 (avril 2007) : 336–40. http://dx.doi.org/10.1109/tim.2007.891137.

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Wang, Qiang, Yi-Ge Lin, Fei Meng, Ye Li, Bai-Ke Lin, Er-Jun Zang, Tian-Chu Li et Zhan-Jun Fang. « Magic Wavelength Measurement of the 87 Sr Optical Lattice Clock at NIM ». Chinese Physics Letters 33, n^o 10 (octobre 2016) : 103201. http://dx.doi.org/10.1088/0256-307x/33/10/103201.

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IDO, Tetsuya, Atsushi YAMAGUCHI et Michi KOIDE. « A Sr Lattice Clock at NICT and A Design of An Optical Cavity to Stabilize Clock Lasers ». Review of Laser Engineering 38, n^o 7 (2010) : 493–99. http://dx.doi.org/10.2184/lsj.38.493.

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MUSHA, Mitsuru. « Frequency Measurement of A Sr Optical Lattice Clock Using A 120-km Precision Optical Fiber Link ». Review of Laser Engineering 38, n^o 7 (2010) : 505–11. http://dx.doi.org/10.2184/lsj.38.505.

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De-Huan, Kong, Guo Feng, Li Ting, Lu Xiao-Tong, Wang Ye-Bing et Chang Hong. « Evaluation of systematic uncertainty for transportable ⁸⁷Sr optical lattice clock ». Acta Physica Sinica 70, n^o 3 (2021) : 030601. http://dx.doi.org/10.7498/aps.70.20201204.

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Hong, F. L., M. Musha, M. Takamoto, H. Inaba, S. Yanagimachi, A. Takamizawa, K. Watabe et al. « Measuring the frequency of a Sr optical lattice clock using a 120 km coherent optical transfer ». Optics Letters 34, n^o 5 (27 février 2009) : 692. http://dx.doi.org/10.1364/ol.34.000692.

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Thèses sur le sujet "Sr optical lattice clock"

Barber, Zeb. « Ytterbium optical lattice clock ». Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3284459.

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He, Wei. « Towards miniaturized strontium optical lattice clock ». Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7460/.

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Optical atomic clocks with precisions and accuracies in the 10$^-$$^1$$^8$ level [1] are now the most advanced man-made timekeeping devices. They outperform the microwave cesium atomic clocks that realize the SI definition of the second. Scaling down the size of optical atomic clocks may open the door to a range of industrial and space applications. In this thesis, the design and preliminary results of a compact strontium cooling system are presented. In the first cooling stage, the high power 461 nm laser with 300 mW output features a modular design, while smaller laser sources for demonstrating a strontium magneto-optical trap have also been investigated. An innovative design that couples a spectroscopy cell directly into the scientific chamber reduces the overall size and power consumption of the system. Additionally, using strontium oxide as a source of strontium atoms suitable for optical clocks has achieved initial success. For the first time, a single-beam MOT configuration is applied to strontium. In this novel apparatus, the blue MOT and red MOT broadband cooling phases are able to trap 5x10$^6$ and 1000 atoms, respectively. This work shows promising progress towards developing a functional miniaturized strontium optical lattice clock.

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Bridge, Elizabeth Michelle. « Towards a strontium optical lattice clock ». Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:a96e73fe-f17b-4738-be1d-34429b5b4a05.

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Due to the recent success, in terms of accuracy and precision, of a number of strontium optical lattice optical frequency standards, and the classification of the 5s² ¹S₀ to 5s5p ³P₀ transition in neutral strontium as a secondary definition of the SI unit of the second, many new strontium lattice clocks are under development. The strontium optical lattice clock (Sr OLC) at the National Physical Laboratory (NPL) is one such project. This thesis describes the design and build of the NPL Sr OLC, discussing the considerations behind the design. Details of the first cooling stage are given, which includes the characterisation of a novel permanent-magnet Zeeman slower by measurements of the longitudinal velocity distributions and loading of the MOT at 461 nm. Development of a narrow linewidth laser system at 689 nm is described, which is used for initial spectroscopy of the second-stage cooling transition. In particular, this work describes progress towards two independent ultra-narrow linewidth clock lasers. The new generation of strontium lattice clock experiments have focused on characterising the systematic frequency shifts and reducing their associated fractional frequency uncertainties, as well as reducing the fractional frequency instability of the measurement. One focus of the Sr OLC at NPL is to help characterise the frequency shift of the clock transition due to black-body radiation (BBR), which is currently the largest contributor to the uncertainty budget of the measured clock frequency. Our approach, discussed here, is to make a direct, differential measurement of the shift with the atoms housed alternately in environments of differing temperatures. Better characterisation and control of the BBR frequency shift of the strontium clock transition is crucial for the future of the Sr OLC as a leading frequency standard.

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Hobson, Richard. « An optical lattice clock with neutral strontium ». Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:d52faaaf-307c-4b48-847f-be590f46136f.

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Strontium optical lattice clocks can measure the passage of time with extraordinary precision. Capitalising on this precision, we can anticipate the deployment of lattice clocks to search for new physics beyond the standard model, to build new technologies for geodesy and navigation, and potentially to underpin a future redenition of the SI second. This thesis reports on the construction and evaluation of a robust Sr optical lattice clock at NPL. We describe the apparatus needed to capture, cool, and load samples of neutral strontium atoms into a magic-wavelength, far off-resonant lattice trap at 813 nm. We provide details of our optical local oscillator - the "clock laser" - and how it is used to realise an Sr-referenced optical frequency standard. We rigorously characterise the various contributing factors which limit the performance of the clock, focusing on the standard measures of (1) frequency instability, and (2) systematic frequency uncertainty. Finally, we introduce new innovations for improving the accuracy of the 88Sr lattice clock, including methods of "modified hyper-Ramsey" and multi-photon spectroscopy of the clock transition.

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Smith, Lyndsie Laura. « A transportable strontium optical lattice clock towards space ». Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/7132/.

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This work presents the realisation and characterisation of the world’s smallest transportable optical lattice clock as part of the Space Optical Clocks 2 EU project built at the University of Birmingham. Housed in a transportable rack of dimensions 170 x 100 x 60 cm, such a device aims to measure the frequency of the doubly-forbidden 1S0−3P0 clock transition in 88Sr in an unprecedented compact apparatus as a major technological milestone towards an optical clock upon the International Space Station. A master optical clock in space would serve with unrivalled accuracy and stability to disseminate a precise and accurate reference for terrestrial clocks and the coordination of international time. Such a clock has the potential to redefine the second, revolutionise timekeeping and precision measurements, and perform fundamental science experiments in space. Using a combination of novel design, innovative cooling techniques, and robust, compact commercially available products, the clock portability, robustness and operational simplicity have been improved. The apparatus simply and effectively cools and traps up to 105 88Sr atoms at a temperature of 1.3±0.2μK in an optical lattice with a lifetime of 0.52±0.01s within 400ms. The most recent preliminary clock spectroscopy measurement was 3.6 ± 0.2Hz. The instability of the clock has been measured at 8×10−17 after averaging for 300s with the goal instability being 5.8×10−17 within the same averaging time. These results show the experiment will lead transportable optical clock research and continue with the goal of being a master clock in space.

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Ludlow, Andrew D. « The strontium optical lattice clock : Optical spectroscopy with sub-hertz accuracy ». Connect to online resource, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3308676.

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Origlia, Stefano [Verfasser]. « A high-performance bosonic optical lattice clock / Stefano Origlia ». Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2018. http://d-nb.info/1169393357/34.

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Abou, Jaoudeh Charbel [Verfasser]. « Setup of a Transportable Yb Optical Lattice Clock / Charbel Abou Jaoudeh ». Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2016. http://d-nb.info/1082033316/34.

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Grotti, Jacopo [Verfasser]. « A transportable optical lattice clock for metrology and geodesy / Jacopo Grotti ». Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2018. http://d-nb.info/1172414173/34.

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Yu, QinQin. « Characterization of a two-color magneto-optical trap for a spin-squeezed optical lattice clock ». Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/100323.

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Thesis: S.B., Massachusetts Institute of Technology, Department of Physics, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 57-58).
We experimentally realize a magneto-optical trap (MOT) for ytterbium that simultaneously scatters light from two atomic transitions, in order to reduce the minimum magnetic field gradient required for trapping atoms. From the experimental data, we propose a model of the MOT where one transition is responsible for trapping the atoms the other transition is responsible for cooling the atoms. In order to test this model and to better understand the dynamics of this two-color MOT, we perform numerical simulations of the contributions of each transition to the steady-state number of trapped atoms. We then compare the results of the simulations with the experimental results and conclude that the model of the separated trapping and cooling functions is a good model for the two-color MOT. Finally, we examine other elements for which the two-color MOT is possible and derive a condition for the linewidths of the two transitions such that the atoms are trapped.
by QinQin Yu.
S.B.

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Chapitres de livres sur le sujet "Sr optical lattice clock"

Tanaka, Yoshiyuki, et Yosuke Aoki. « A Geodetic Determination of the Gravitational Potential Difference Toward a 100-km-Scale Clock Frequency Comparison in a Plate Subduction Zone ». Dans International Association of Geodesy Symposia. Berlin, Heidelberg : Springer Berlin Heidelberg, 2022. http://dx.doi.org/10.1007/1345_2022_147.

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AbstractRecent advances in the developments of optical atomic clocks have enabled 10−18-level frequency comparisons between fibre-linked clocks. Therefore, chronometric leveling with an uncertainty on the order of 1 cm has become possible, based on the general theory of relativity. Since measurement uncertainty does not deteriorate with increasing fibre length, applications of chronometric leveling in geodesy, particularly unification of height reference systems, have been actively studied. In Japan, a frequency comparison is under experimentation using a fibre link connecting two optical lattice clocks approximately 100 km apart. This study estimates both the potential difference between these two clock sites with a geodetic method and its uncertainty to verify the results of chronometric leveling, which will be obtained in the near future. We use orthometric heights derived from leveling surveys repeated for monitoring crustal deformation. When discussing an uncertainty at the 1-cm level in height, the effects of temporal variations in the gravitational potential on the height measurement need to be considered due to various geophysical phenomena, including tides. Our results show that the uncertainty in the height measurements by geodetic leveling is the largest and that tidal potential changes during the height measurements can cause systematic errors of a few mm. The effects due to variations in the nontidal ocean bottom pressure and atmospheric pressure are more than an order of magnitude smaller than the tidal effects at this spatial scale. An upper limit of groundwater effects is also estimated. In a future comparison with clocks with an uncertainty on the order of 10−19, tidal potential changes and groundwater effects must be more rigorously evaluated.

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Actes de conférences sur le sujet "Sr optical lattice clock"

WESTERGAARD, P. G., A. LECALLIER, J. LODEWYCK et P. LEMONDE. « OPTICAL LATTICE CLOCK WITH Sr ATOMS ». Dans Proceedings of the 7th Symposium. WORLD SCIENTIFIC, 2009. http://dx.doi.org/10.1142/9789812838223_0022.

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Ye, Jun. « Optical clock with lattice-confined Sr atoms ». Dans Laser Science. Washington, D.C. : OSA, 2010. http://dx.doi.org/10.1364/ls.2010.lwb2.

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Poli, Nicola, Marco G. Tarallo, Marco Schioppo, Christopher W. Oates et Guglielmo M. Tino. « An optical lattice clock based on bosonic Sr ». Dans 2009 Joint Meeting of the European Frequency and Time Forum (EFTF) and the IEEE International Frequency Control Symposium (FCS). IEEE, 2009. http://dx.doi.org/10.1109/freq.2009.5168199.

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Baillard, X., M. Fouche, R. le Targat, P. G. Westergaard, A. Lecallier, F. Chapelet, S. Bize et al. « An Optical Lattice Clock with Fermionic and Bosonic Sr Atoms ». Dans 2007 Conference on Lasers and Electro-Optics - Pacific Rim. IEEE, 2007. http://dx.doi.org/10.1109/cleopr.2007.4391551.

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Le Targat, R., X. Brusch, X. Baillard, M. Fouche et P. Lemonde. « Higher order frequency shifts in a Sr optical lattice clock ». Dans 2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference. IEEE, 2006. http://dx.doi.org/10.1109/cleo.2006.4627841.

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Foreman, S. M., M. M. Boyd, A. D. Ludlow, T. Zelevinsky, S. Blatt, T. Ido et J. Ye. « High Spectral Resolution and Accuracy Studies for a Sr Optical Lattice Clock ». Dans Proceedings of the 2006 IEEE International Frequency Control Symposium and Exposition. IEEE, 2006. http://dx.doi.org/10.1109/freq.2006.275367.

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Bilicki, Slawomir, Eva Bookjans, Gregoire Vallet, Michel Abgrall, Rodolphe Le Targat et Jerome Lodewyck. « Contributing to TAI with Sr optical lattice clocks ». Dans 2017 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium ((EFTF/IFC). IEEE, 2017. http://dx.doi.org/10.1109/fcs.2017.8089044.

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Daisuke Akamatsu, Masami Yasuda, Takuya Kohno, Kazumoto Hosaka, Hajime Inaba, Yoshiaki Nakajima et Feng-Lei Hong. « Toward the Yb/Sr frequency ratio measurement : Development of the Sr optical lattice clock at NMIJ, AIST ». Dans 2010 Conference on Precision Electromagnetic Measurements (CPEM 2010). IEEE, 2010. http://dx.doi.org/10.1109/cpem.2010.5545275.

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Cifuentes Marin, Miguel A., Haosen Shang, Yannick Foucault, Rodolphe Le Targat et Jerome Lodewyck Lne-Syrte. « Generating Laguerre-Gaussian Modes for Atom Trapping in a Sr Optical Lattice Clock ». Dans 2022 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS). IEEE, 2022. http://dx.doi.org/10.1109/eftf/ifcs54560.2022.9850746.

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Hisai, Yusuke, Daisuke Akamatsu, Takumi Kobayashi, Kazumoto Hosaka, Hajime Inaba, Feng-Lei Hong et Masami Yasuda. « Sr optical lattice clock assisted by optical frequency combs for contribution to International Atomic Time ». Dans CLEO : Science and Innovations. Washington, D.C. : OSA, 2020. http://dx.doi.org/10.1364/cleo_si.2020.sth3g.2.

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Rapports d'organisations sur le sujet "Sr optical lattice clock"

Lemke, N. D. An Optical Lattice Clock with Spin 1/2 Atoms. Fort Belvoir, VA : Defense Technical Information Center, janvier 2012. http://dx.doi.org/10.21236/ad1007299.

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Rey, A. M., A. V. Gorshkov, C. V. Kraus, M. J. Martin, M. Bishof, M. D. Swallows, X. Zhang et al. Probing Many-Body Interactions in an Optical Lattice Clock (Preprint). Fort Belvoir, VA : Defense Technical Information Center, octobre 2013. http://dx.doi.org/10.21236/ada604165.

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