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Tetsuya Ido

Bio: Tetsuya Ido is an academic researcher from National Institute of Information and Communications Technology. The author has contributed to research in topics: Atomic clock & Population. The author has an hindex of 32, co-authored 115 publications receiving 3099 citations. Previous affiliations of Tetsuya Ido include University of Colorado Boulder & National Presto Industries.


Papers
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Journal ArticleDOI
TL;DR: In this article, a narrow-line laser cooling and trapping of strontium atoms down to the photon recoil temperature was reported, achieving a maximum phase space density of 3 orders of magnitude larger than the value obtained by magneto-optical traps to date.
Abstract: We report narrow-line laser cooling and trapping of strontium atoms down to the photon recoil temperature. ${}^{88}\mathrm{Sr}$ atoms precooled by the broad $^{1}S_{0}\ensuremath{-}^{1}P_{1}$ transition at 461 nm were further cooled in a magneto-optical trap using the spin-forbidden transition $^{1}S_{0}\ensuremath{-}^{3}P_{1}$ at 689 nm. We have thus obtained an atomic sample with a density over ${10}^{12}\mathrm{cm}{}^{\ensuremath{-}3}$ and a minimum temperature of 400 nK, corresponding to a maximum phase space density of ${10}^{\ensuremath{-}2}$ which is 3 orders of magnitude larger than the value that has been obtained by magneto-optical traps to date. This scheme provides us an opportunity and system to study quantum statistical properties of degenerate fermions as well as bosons.

323 citations

Journal ArticleDOI
TL;DR: In this article, the overall systematic uncertainty of the Cs-fountain primary standard for lattice-confined clock resonance has been characterized to $9\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}15}$.
Abstract: Aided by ultrahigh resolution spectroscopy, the overall systematic uncertainty of the $^{1}S_{0}\mathrm{\text{\ensuremath{-}}}^{3}P_{0}$ clock resonance for lattice-confined $^{87}\mathrm{Sr}$ has been characterized to $9\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}16}$. This uncertainty is at a level similar to the Cs-fountain primary standard, while the potential stability for the lattice clocks exceeds that of Cs. The absolute frequency of the clock transition has been measured to be 429 228 004 229 874.0(1.1) Hz, where the $2.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}15}$ fractional uncertainty represents the most accurate measurement of a neutral-atom-based optical transition frequency to date.

162 citations

Journal ArticleDOI
01 Dec 2006-Science
TL;DR: In this article, an optical approach for excitation of nuclear spin states was proposed to reveal optical resonance linewidths at the hertz level with a good signal-to-noise ratio.
Abstract: Highest-resolution laser spectroscopy has generally been limited to single trapped ion systems because of the rapid decoherence that plagues neutral atom ensembles. Precision spectroscopy of ultracold neutral atoms confined in a trapping potential now shows superior optical coherence without any deleterious effects from motional degrees of freedom, revealing optical resonance linewidths at the hertz level with a good signal-to-noise ratio. The resonance quality factor of 2.4 × 1014 is the highest ever recovered in any form of coherent spectroscopy. The spectral resolution permits direct observation of the breaking of nuclear spin degeneracy for the 1S and 3P optical clock states of 87Sr under a small magnetic bias field. This optical approach for excitation of nuclear spin states allows an accurate measurement of the differential Lande g factor between 1S and 3P. The optical atomic coherence demonstrated for collective excitation of a large number of atoms will have a strong impact on quantum measurement and precision frequency metrology.

148 citations

Journal ArticleDOI
TL;DR: This work presents the most precise study to date of the 1S0-3P0 optical clock transition with a detailed analysis of systematic shifts in the absolute frequency measurement of 429 228 004 229 869 Hz.
Abstract: 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.

135 citations

Journal ArticleDOI
TL;DR: A dynamic magneto-optical trap, which relies on the rapid randomization of population in Zeeman substates, has been demonstrated for fermionic strontium atoms on the 1S0-3P1 intercombination transition.
Abstract: A dynamic magneto-optical trap, which relies on the rapid randomization of population in Zeeman substates, has been demonstrated for fermionic strontium atoms on the $^{1}S_{0}\ensuremath{-}^{3}P_{1}$ intercombination transition. The obtained sample, $1\ifmmode\times\else\texttimes\fi{}{10}^{6}$ atoms at a temperature of $2\text{ }\ensuremath{\mu}\mathrm{K}$ in the trap, was further Doppler cooled and polarized in a far-off resonant optical lattice to achieve 2 times the Fermi temperature.

127 citations


Cited by
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Journal ArticleDOI
TL;DR: Feshbach resonances are the essential tool to control the interaction between atoms in ultracold quantum gases and have found numerous experimental applications, opening up the way to important breakthroughs as mentioned in this paper.
Abstract: Feshbach resonances are the essential tool to control the interaction between atoms in ultracold quantum gases. They have found numerous experimental applications, opening up the way to important breakthroughs. This review broadly covers the phenomenon of Feshbach resonances in ultracold gases and their main applications. This includes the theoretical background and models for the description of Feshbach resonances, the experimental methods to find and characterize the resonances, a discussion of the main properties of resonances in various atomic species and mixed atomic species systems, and an overview of key experiments with atomic Bose-Einstein condensates, degenerate Fermi gases, and ultracold molecules.

2,642 citations

01 May 2009
TL;DR: Feshbach resonances are the essential tool to control the interaction between atoms in ultracold quantum gases and have found numerous experimental applications, opening up the way to important breakthroughs as mentioned in this paper.
Abstract: Feshbach resonances are the essential tool to control the interaction between atoms in ultracold quantum gases. They have found numerous experimental applications, opening up the way to important breakthroughs. This review broadly covers the phenomenon of Feshbach resonances in ultracold gases and their main applications. This includes the theoretical background and models for the description of Feshbach resonances, the experimental methods to find and characterize the resonances, a discussion of the main properties of resonances in various atomic species and mixed atomic species systems, and an overview of key experiments with atomic Bose-Einstein condensates, degenerate Fermi gases, and ultracold molecules.

1,531 citations

Journal ArticleDOI
22 Jan 2014-Nature
TL;DR: 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.
Abstract: In the search for stable and accurate atomic clocks, many-atom lattice clocks have shown higher precision than clocks based on single trapped ions, but have been less accurate; here, a stable many-atom clock is demonstrated that has accuracy better than single-ion clocks. Whether for the definition of SI units, testing the laws of physics or for applications yet to be dreamt of, scientists will always want more stability and more accuracy in their atomic clocks. Many-atom lattice clocks have achieved better precision than clocks based on single trapped ions, but their accuracy has so far been relatively poor. This study from the National Institute of Standards and Technology (NIST) demonstrates a many-atom clock that achieves better accuracy than single-ion-based clocks, and at the same time reduces the required measurement time by two orders of magnitude. Based on thousands of neutral strontium atoms trapped in a laser beam, this new 'optical lattice' clock has the stability, reproducibility and accuracy that make it a prime contender for consideration as a primary standard. It would neither gain nor lose one second in about 5 billion years — although the Earth is unlikely to last that long. Progress in atomic, optical and quantum science1,2 has led to rapid improvements in atomic clocks. At the same time, atomic clock research has helped to advance the frontiers of science, affecting both fundamental and applied research. The ability to control quantum states of individual atoms and photons is central to quantum information science and precision measurement, and optical clocks based on single ions have achieved the lowest systematic uncertainty of any frequency standard3,4,5. Although many-atom lattice clocks have shown advantages in measurement precision over trapped-ion clocks6,7, their accuracy has remained 16 times worse8,9,10. Here we demonstrate 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. By systematically evaluating all known sources of uncertainty, including in situ monitoring of the blackbody radiation environment, we improve the accuracy of optical lattice clocks by a factor of 22. This single clock has simultaneously achieved the best known performance in the key characteristics necessary for consideration as a primary standard—stability and accuracy. More stable and accurate atomic clocks will benefit a wide range of fields, such as the realization and distribution of SI units11, the search for time variation of fundamental constants12, clock-based geodesy13 and other precision tests of the fundamental laws of nature. This work also connects to the development of quantum sensors and many-body quantum state engineering14 (such as spin squeezing) to advance measurement precision beyond the standard quantum limit.

939 citations

Journal ArticleDOI
TL;DR: In this article, the authors review progress in understanding the nature of atomic collisions occurring at temperatures ranging from the millidegrees Kelvin to the nanodegree Kelvin regime, including advances in experiments with atom beams, light traps, and purely magnetic traps.
Abstract: The authors review progress in understanding the nature of atomic collisions occurring at temperatures ranging from the millidegrees Kelvin to the nanodegrees Kelvin regime. The review includes advances in experiments with atom beams, light traps, and purely magnetic traps. Semiclassical and fully quantal theories are described and their appropriate applicability assessed. The review divides the subject into two principal categories: collisions in the presence of one or more light fields and ground-state collisions in the dark.

790 citations

Journal ArticleDOI
TL;DR: In this paper, the authors describe the discovery and study of BoseEinstein condensates (BECs) in atomic gases from a personal perspective, and describe how they were used to explore quantum-degenerate gases, such as BECs first realized in 1995.
Abstract: The lure of lower temperatures has attracted physicists for the past century, and with each advance towards absolute zero, new and rich physics has emerged. Laypeople may wonder why ‘‘freezing cold’’ is not cold enough. But imagine how many aspects of nature we would miss if we lived on the surface of the sun. Without inventing refrigerators, we would only know gaseous matter and never observe liquids or solids, and miss the beauty of snowflakes. Cooling to normal earthly temperatures reveals these dramatically different states of matter, but this is only the beginning: many more states appear with further cooling. The approach into the kelvin range was rewarded with the discovery of superconductivity in 1911 and of superfluidity in helium-4 in 1938. Cooling into the millikelvin regime revealed the superfluidity of helium-3 in 1972. The advent of laser cooling in the 1980s opened up a new approach to ultralow-temperature physics. Microkelvin samples of dilute atom clouds were generated and used for precision measurements and studies of ultracold collisions. Nanokelvin temperatures were necessary to explore quantum-degenerate gases, such as Bose-Einstein condensates first realized in 1995. Each of these achievements in cooling has been a major advance, and recognized with a Nobel prize. This paper describes the discovery and study of BoseEinstein condensates (BEC’s) in atomic gases from my personal perspective. Since 1995, this field has grown explosively, drawing researchers from the communities of atomic physics, quantum optics, and condensedmatter physics. The trapped ultracold vapor has emerged as a new quantum system that is unique in the precision and flexibility with which it can be controlled and manipulated. At least 30 groups have now created condensates, and the publication rate on Bose-Einstein condensation has soared following the discovery of the gaseous condensates in 1995 (see Fig. 1).

763 citations