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Hidetoshi Katori - One of the best experts on this subject based on the ideXlab platform.
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Optical Lattice Clocks for Precision Time and Frequency Metrology
Principles and Methods of Quantum Information Technologies, 2016Co-Authors: Masao Takamoto, Hidetoshi KatoriAbstract:An Optical Lattice operated at the “magic wavelength” provides a platform for precision metrology of time and frequency, where an atomic ensemble serves as a reference with precisely-controlled quantum states. Such an Optical Lattice clock allows extremely high accuracy and stability at the level of 10−18. This review outlines the principles and experimental realization of Optical Lattice clocks, in particular, the demonstration of quantum projection noise limited stability and the reduction of the uncertainty induced by the blackbody radiation. As a future prospect, we discuss the application of Optical Lattice clocks as a tool for relativistic geodesy.
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Cryogenic Optical Lattice clocks
Nature Photonics, 2015Co-Authors: Ichiro Ushijima, Masao Takamoto, Manoj Das, Takuya Ohkubo, Hidetoshi KatoriAbstract:The accuracy of atomic clocks relies on the superb reproducibility of atomic spectroscopy, which is accomplished by careful control and the elimination of environmental perturbations on atoms. To date, individual atomic clocks have achieved a 10^−18 level of total uncertainties^ 1 , 2 , but a two-clock comparison at the 10^−18 level has yet to be demonstrated. Here, we demonstrate Optical Lattice clocks with ^87Sr atoms interrogated in a cryogenic environment to address the blackbody radiation-induced frequency shift^ 3 , which remains the primary source of systematic uncertainty^ 2 , 4 , 5 , 6 and has initiated vigorous theoretical^ 7 , 8 and experimental^ 9 , 10 investigations. The systematic uncertainty for the cryogenic clock is evaluated to be 7.2 × 10^−18, which is expedited by operating two such cryo-clocks synchronously^ 11 , 12 . After 11 measurements performed over a month, statistical agreement between the two cryo-clocks reached 2.0 × 10^−18. Such clocks' reproducibility is a major step towards developing accurate clocks at the low 10^−18 level, and is directly applicable as a means for relativistic geodesy^ 13 . A pair of ^87Sr Optical Lattice clocks with a statistical agreement of 2 × 10^−18 within 6,000 s has been developed. To this end, the behaviour of the blackbody radiation—a major perturbation for Optical Lattice clocks—was directly investigated.
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Cryogenic Optical Lattice clocks
Nature Photonics, 2015Co-Authors: Ichiro Ushijima, Masao Takamoto, Manoj Das, Takuya Ohkubo, Hidetoshi KatoriAbstract:A pair of 87Sr Optical Lattice clocks with a statistical agreement of 2 × 10−18 within 6,000 s has been developed. To this end, the behaviour of the blackbody radiation—a major perturbation for Optical Lattice clocks—was directly investigated.
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Frequency comparison of Optical Lattice clocks
Time and Frequency Metrology III, 2011Co-Authors: Masao Takamoto, Tetsushi Takano, Hidetoshi KatoriAbstract:We demonstrate the frequency comparison of two Optical Lattice clocks at the relative stabilities close to the quantum projection noise (QPN) limit of Optical Lattice clocks. This stable frequency comparison is accomplished by synchronous interrogations of two clocks by a common probe laser, which allows us to cancel out the probe laser's frequency noise. We perform the frequency comparison of a one-dimensional (1D) Optical Lattice clock with spin-polarized fermions 87Sr and a three-dimensional (3D) Optical Lattice clock with unity-occupation bosons 88Sr and achieve the Allan standard deviation of σγ(τ)=4×10-16 τ-1/2, which corresponds to the QPN limited stability for N =1,000 atoms and the spectrum linewidth γ=8 Hz. The relative stability reaches 1×10-17 with an averaging time of 1,600 s. Finally, we discuss the prospects to realize 10-18 fractional inaccuracies and the possible application of frequency comparison with synchronous interrogations to remote clocks' comparison for relativistic geodesy.© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
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Colloquium: Physics of Optical Lattice clocks
Reviews of Modern Physics, 2011Co-Authors: Andrei Derevianko, Hidetoshi KatoriAbstract:Recently invented and demonstrated Optical Lattice clocks hold great promise for improving the precision of modern time keeping. These clocks aim at the ${10}^{\ensuremath{-}18}$ fractional accuracy, which translates into a clock that would neither lose nor gain a fraction of a second over an estimated age of the Universe. In these clocks, millions of atoms are trapped and interrogated simultaneously, dramatically improving clock stability. Here the principles of operation of these clocks are discussed and, in particular, a novel concept of magic trapping of atoms in Optical Lattices. Recently proposed microwave Lattice clocks are also highlights and several applications that employ the Optical Lattice clocks as a platform for precision measurements and quantum information processing.
Masao Takamoto - One of the best experts on this subject based on the ideXlab platform.
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Optical Lattice Clocks for Precision Time and Frequency Metrology
Principles and Methods of Quantum Information Technologies, 2016Co-Authors: Masao Takamoto, Hidetoshi KatoriAbstract:An Optical Lattice operated at the “magic wavelength” provides a platform for precision metrology of time and frequency, where an atomic ensemble serves as a reference with precisely-controlled quantum states. Such an Optical Lattice clock allows extremely high accuracy and stability at the level of 10−18. This review outlines the principles and experimental realization of Optical Lattice clocks, in particular, the demonstration of quantum projection noise limited stability and the reduction of the uncertainty induced by the blackbody radiation. As a future prospect, we discuss the application of Optical Lattice clocks as a tool for relativistic geodesy.
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Cryogenic Optical Lattice clocks
Nature Photonics, 2015Co-Authors: Ichiro Ushijima, Masao Takamoto, Manoj Das, Takuya Ohkubo, Hidetoshi KatoriAbstract:The accuracy of atomic clocks relies on the superb reproducibility of atomic spectroscopy, which is accomplished by careful control and the elimination of environmental perturbations on atoms. To date, individual atomic clocks have achieved a 10^−18 level of total uncertainties^ 1 , 2 , but a two-clock comparison at the 10^−18 level has yet to be demonstrated. Here, we demonstrate Optical Lattice clocks with ^87Sr atoms interrogated in a cryogenic environment to address the blackbody radiation-induced frequency shift^ 3 , which remains the primary source of systematic uncertainty^ 2 , 4 , 5 , 6 and has initiated vigorous theoretical^ 7 , 8 and experimental^ 9 , 10 investigations. The systematic uncertainty for the cryogenic clock is evaluated to be 7.2 × 10^−18, which is expedited by operating two such cryo-clocks synchronously^ 11 , 12 . After 11 measurements performed over a month, statistical agreement between the two cryo-clocks reached 2.0 × 10^−18. Such clocks' reproducibility is a major step towards developing accurate clocks at the low 10^−18 level, and is directly applicable as a means for relativistic geodesy^ 13 . A pair of ^87Sr Optical Lattice clocks with a statistical agreement of 2 × 10^−18 within 6,000 s has been developed. To this end, the behaviour of the blackbody radiation—a major perturbation for Optical Lattice clocks—was directly investigated.
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Cryogenic Optical Lattice clocks
Nature Photonics, 2015Co-Authors: Ichiro Ushijima, Masao Takamoto, Manoj Das, Takuya Ohkubo, Hidetoshi KatoriAbstract:A pair of 87Sr Optical Lattice clocks with a statistical agreement of 2 × 10−18 within 6,000 s has been developed. To this end, the behaviour of the blackbody radiation—a major perturbation for Optical Lattice clocks—was directly investigated.
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Frequency comparison of Optical Lattice clocks
Time and Frequency Metrology III, 2011Co-Authors: Masao Takamoto, Tetsushi Takano, Hidetoshi KatoriAbstract:We demonstrate the frequency comparison of two Optical Lattice clocks at the relative stabilities close to the quantum projection noise (QPN) limit of Optical Lattice clocks. This stable frequency comparison is accomplished by synchronous interrogations of two clocks by a common probe laser, which allows us to cancel out the probe laser's frequency noise. We perform the frequency comparison of a one-dimensional (1D) Optical Lattice clock with spin-polarized fermions 87Sr and a three-dimensional (3D) Optical Lattice clock with unity-occupation bosons 88Sr and achieve the Allan standard deviation of σγ(τ)=4×10-16 τ-1/2, which corresponds to the QPN limited stability for N =1,000 atoms and the spectrum linewidth γ=8 Hz. The relative stability reaches 1×10-17 with an averaging time of 1,600 s. Finally, we discuss the prospects to realize 10-18 fractional inaccuracies and the possible application of frequency comparison with synchronous interrogations to remote clocks' comparison for relativistic geodesy.© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
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Optical Lattice clocks and frequency comparison
Journal of Physics: Conference Series, 2011Co-Authors: Hidetoshi Katori, Tetsushi Takano, Masao TakamotoAbstract:We consider designs of Optical Lattice clocks in view of the quantum statistics, relevant atomic spins, and atom-Lattice interactions. The first two issues lead to two optimal constructions for the clock: a one-dimensional (1D) Optical Lattice loaded with spin-polarized fermions and a 3D Optical Lattice loaded with bosons. By taking atomic multipolar interactions with the Lattice fields into account, an atomic motion insensitive wavelength is proposed to provide a precise definition of the magic wavelength. We then present a frequency comparison of these two Optical Lattice clocks: spin-polarized fermionic 87Sr and bosonic 88Sr prepared in 1D and 3D Optical Lattices, respectively. Synchronous interrogations of these two Optical Lattice clocks by the same probe laser allowed canceling out its frequency noise as a common mode noise to achieve a relative stability of 3?10?17 for an averaging time of ? = 350 s. The scheme, therefore, provides us with a powerful means to investigate intrinsic uncertainty of the clocks regardless of the probe laser stability. We discuss prospects of the synchronous operation of the clocks on the measurement of the geoid height difference and on the search of constancy of fundamental constants.
Andrew D. Ludlow - One of the best experts on this subject based on the ideXlab platform.
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spin 1 2 Optical Lattice clock
Physical Review Letters, 2009Co-Authors: Nathan D Lemke, Andrew D. Ludlow, Z. W. Barber, Tara M Fortier, Scott A Diddams, Yanyi Jiang, S R Jefferts, T P Heavner, Thomas E Parker, C W OatesAbstract:We experimentally investigate an Optical clock based on {sup 171}Yb (I=1/2) atoms confined in an Optical Lattice. We have evaluated all known frequency shifts to the clock transition, including a density-dependent collision shift, with a fractional uncertainty of 3.4x10{sup -16}, limited principally by uncertainty in the blackbody radiation Stark shift. We measured the absolute clock transition frequency relative to the NIST-F1 Cs fountain clock and find the frequency to be 518 295 836 590 865.2(0.7) Hz.
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spin 1 2 Optical Lattice clock
arXiv: Atomic Physics, 2009Co-Authors: Nathan D Lemke, Andrew D. Ludlow, Z. W. Barber, Tara M Fortier, Scott A Diddams, Yanyi Jiang, S R Jefferts, T P Heavner, Thomas E Parker, C W OatesAbstract:We experimentally investigate an Optical clock based on $^{171}$Yb ($I=1/2$) atoms confined in an Optical Lattice. We have evaluated all known frequency shifts to the clock transition, including a density-dependent collision shift, with a fractional uncertainty of $3.4 \times 10^{-16}$, limited principally by uncertainty in the blackbody radiation Stark shift. We measured the absolute clock transition frequency relative to the NIST-F1 Cs fountain clock and find the frequency to be 518 295 836 590 865.2(0.7) Hz.
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Optical Lattice clock with ultracold strontium atoms
2006Co-Authors: Martin M. Boyd, Andrew D. Ludlow, Tanya Zelevinsky, Seth M. Foreman, Sebastian Blatt, Tetsuya IdoAbstract:We report recent progress on an Optical atomic clock based on the ultranarrow 1S 0 -3P 0 transition in fermionic neutral strontium atoms confined in an Optical Lattice. A detailed systematic study of the clock transition frequency is presented along with the recent improvement in the measured line quality factor which is expected to lead to an accuracy of 10−15 or better in the near future.
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Systematic Study of the 87Sr Clock Transition in an Optical Lattice
Physical review letters, 2006Co-Authors: Andrew D. Ludlow, Martin M. Boyd, Tanya Zelevinsky, Seth M. Foreman, Sebastian Blatt, Mark Notcutt, Tetsuya IdoAbstract:With ultracold 87Srconfined in a magic wavelength Optical Lattice, we present the most precise study (2.8 Hz statistical uncertainty) to date of the 1S0-3P0 Optical clock transition with a detailed analysis of systematic shifts (19 Hz uncertainty) in the absolute frequency measurement of 429 228 004 229 869 Hz. The high resolution permits an investigation of the Optical Lattice motional sideband structure. The local oscillator for this Optical atomic clock is a stable diode laser with its hertz-level linewidth characterized by an octave-spanning femtosecond frequency comb.
Pierre Lemonde - One of the best experts on this subject based on the ideXlab platform.
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Frequency stability of Optical Lattice clocks
New Journal of Physics, 2010Co-Authors: Jérôme Lodewyck, Philip G. Westergaard, Arnaud Lecallier, Luca Lorini, Pierre LemondeAbstract:In this paper, we review several aspects of the frequency stability of Optical Lattice clocks. We describe a new ultra-stable cavity design with reduced thermal noise and record frequency stability (below 10 15 ), as well as a non-destructive detection scheme for measuring the clock transition probability. Given the experimental parameters we measured, we simulate different sequence strategies for optimizing the stability. Finally, we report on the development of a second Optical Lattice clock and simulate several comparison strategies. In particular, we show by a numerical method that a stability as low as 2◊10 16 1/2 can be reached with Optical Lattice clocks, and we show how to demonstrate this stability with a double clock system.
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Optical Lattice clocks
The European Physical Journal Special Topics, 2009Co-Authors: Pierre LemondeAbstract:The Idea of using cold atoms confined in an Optical Lattice for an Optical clock was proposed in 2001 [1]. Since then, this idea became an experimental reality. We review here the contribution of LNE-SYRTE to these developments.
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An accurate Optical Lattice clock with 87Sr atoms
2006Co-Authors: R. Le Targat, A. Brusch, Xavier Baillard, Mathilde Hugbart, Olivier Tcherbakoff, Giovanni D. Rovera, Pierre LemondeAbstract:We report a frequency measurement of the 1S0-3P0 transition of 87Sr atoms in an Optical Lattice clock. The frequency is determined to be 429 228 004 229 879 (5) Hz with a fractional uncertainty that is comparable to state-of-the-art Optical clocks with neutral atoms in free fall. Two previous measurements of this transition were found to disagree by about 2x10^{-13}, i.e. almost four times the combined error bar, instilling doubt on the potential of Optical Lattice clocks to perform at a high accuracy level. In perfect agreement with one of these two values, our measurement essentially dissipates this doubt.
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An Optical Lattice clock with strontium atoms
2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, 2006Co-Authors: Mathilde Fouché, R. Le Targat, A. Brusch, Xavier Baillard, Pierre LemondeAbstract:We report the preliminary operation of an Optical Lattice clock with Sr atoms. We describe a novel method for loading the Lattice and report an Optical resonance of width 260 Hz.
Tetsuya Ido - One of the best experts on this subject based on the ideXlab platform.
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Optical Lattice Clock
MAPAN, 2012Co-Authors: Tetsuya IdoAbstract:Latest progress in Optical atomic clocks is so rapid that serious discussions toward the redefinition of the second is initiated. Besides single ion clocks developed since early 1980s, Optical Lattice clocks just invented a decade ago are one of strong candidates as a method to realize the revised definition. The current situation of this emerging method of Optical clocks is briefly described.
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Optical Lattice clock with ultracold strontium atoms
2006Co-Authors: Martin M. Boyd, Andrew D. Ludlow, Tanya Zelevinsky, Seth M. Foreman, Sebastian Blatt, Tetsuya IdoAbstract:We report recent progress on an Optical atomic clock based on the ultranarrow 1S 0 -3P 0 transition in fermionic neutral strontium atoms confined in an Optical Lattice. A detailed systematic study of the clock transition frequency is presented along with the recent improvement in the measured line quality factor which is expected to lead to an accuracy of 10−15 or better in the near future.
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Systematic Study of the 87Sr Clock Transition in an Optical Lattice
Physical review letters, 2006Co-Authors: Andrew D. Ludlow, Martin M. Boyd, Tanya Zelevinsky, Seth M. Foreman, Sebastian Blatt, Mark Notcutt, Tetsuya IdoAbstract:With ultracold 87Srconfined in a magic wavelength Optical Lattice, we present the most precise study (2.8 Hz statistical uncertainty) to date of the 1S0-3P0 Optical clock transition with a detailed analysis of systematic shifts (19 Hz uncertainty) in the absolute frequency measurement of 429 228 004 229 869 Hz. The high resolution permits an investigation of the Optical Lattice motional sideband structure. The local oscillator for this Optical atomic clock is a stable diode laser with its hertz-level linewidth characterized by an octave-spanning femtosecond frequency comb.
