Science Goals of the Primary Atomic Reference Clock in Space

The PARCS (Primary Atomic Reference Clock in Space) experiment will use a laser-cooled Cesium atomic clock operating in the microgravity environment aboard the International Space Station (ISS) to provide both advanced tests of gravitational theory and to demonstrate a new cold-atom clock technology for space. PARCS is a joint project of the …

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Three-dimensional cooling of cesium atoms in a reflecting copper ...

The technique used in this experiment greatly simplifies the generation of laser-cooled atoms and the damping of atomic motion has lead to temperatures as low as 3.5muK. We present what is to our knowledge the first observation of spin-polarized atoms cooled within a reflecting cylinder in a high-power medium. A low-pressure vapor of cesium atoms is stored in …

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PARCS: A LASER-COOLED ATOMIC CLOCK IN SPACE* - NIST

this experiment include a laser-cooled cesium atomic clock and a GPS frequency-comparison and orbit determination system, along with a hydrogen maser that serves as both a local oscillator for the cesium clock and a reference against which certain tests …

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Three-dimensional cooling of cesium atoms in a reflecting …

We present what is to our knowledge the first observation of spin-polarized atoms cooled within a reflecting cylinder in a high-power medium. A low-pressure vapor of cesium atoms is stored in a glass cell whose volume is 58 cm(3). Cooling laser light (lambda=852 nm) is injected into the cell by opti …

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Bright, slow, and continuous beam of laser-cooled cesium atoms

Abstract. By the moving molasses technique we have extracted laser-cooled cesium atoms in a continuous way directly from an optical molasses. The mean launching velocity is precisely tunable from 1 to 12 m/s. The atomic beam has a flux of 1.3×108 atom/s at 7 m/s and a longitudinal temperature of 70 μK, which represents the highest flux and ...

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Laser-Cooled Atoms: Cesium | ScienceBlogs

Happily, cesium has a laser cooling transition in the near infrared, at 854 nm, which is a relatively convenient laser wavelength. And, …

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Observation of the cesium clock transition in laser-cooled atoms

We have used the light from diode lasers to produce a nearly stationary (upsilon ~ 15 cm/sec) sample of atomic cesium in optical molasses that is entirely in the F = 3 hyperfine state. In this sample we excite the 9.2-GHz 6SF = 3, m = 0 to F = 4, m = 0 clock transition. Most of the atoms remain for ~20 msec in the 0.4-cm(3) observation region.

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Microwave interrogation of cesium atoms cooled in isotropic light ...

Describes here a configuration of an atomic clock using a source of cesium atoms cooled with isotropic light. This three-dimensional (3-D)-cooling scheme yields a number of atoms of nearly 10/sup 9/ with a temperature below 100 /spl mu/K. These values are suitable for metrological applications. We present the preliminary results obtained and give a first estimation of the …

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Testing Lorentz Invariance with Laser-Cooled Cesium Atomic …

Testing Lorentz Invariance with Laser-Cooled Cesium Atomic Frequency Standards This slide presentation reviews the Lorentz invariance testing during the proposed PARCS experiment. It includes information on the primary atomic reference clock in space (PARCS), cesium, laser cooling, and the vision for the future.

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Measure Journal Volume 2 Article 34 NCSL International

NIST-F2, a second-generation atomic fountain standard now being built, promises even better accuracy. This paper explores both the history and the technology of NIST primary frequency standards, beginning in the pre-atomic era and continuing through the present day. (Print: ISSN 1931-5775) (Online: ISSN 2381-0580) ©2007 NCSL International.

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PROGRESS TOWARDS A LASER-COOLED CESIUM ATOMIC …

an atomic frequency standard using a fountain of laser- cooled cesium atoms. We have recently observed Ramsey fringes on the 9.2 GHz clock transition and have begun preliminary work aimed at characterizing our fountain. This paper will describe the apparatus briefly, discuss our current work and near-term directions.

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If you cooled an atomic clock to just above absolute zero, how would …

Answer: Currently, the most accurate atomic clocks first cool the atoms to near zero kelvin temperature by slowing them with lasers and probing them in atomic fountains in a microwave-filled cavity. The accuracy of an atomic clock depends on two factors. 1. The first factor is temperature of th...

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Science Goals of the Primary Atomic Reference Clock in Space …

a laser-cooled Cesium atomic clock operating in the microgravity environment aboard the International Space Station (ISS) to provide both advanced tests of gravitational theory and to demonstrate a new cold-atom clock technology for space. PARCS is a joint project of the National Institute of Standards and Tech-

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What is a "cesium atomic clock"? - National Research Council …

A cesium atomic clock needs a few other parts. Simple electronics counts the output cycles of the quartz oscillator, and issues a pulse every 10 million cycles - exactly 1 second apart. When first started, the atomic clock's time is set with respect to International Atomic Time (TAI, Temps Atomique International) - which has been kept by ...

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NIST-F1 Cesium Fountain Atomic Clock | NIST

The lasers gently push the cesium atoms together into a ball. In the process of creating this ball, the lasers slow down the movement of the atoms and cool them to temperatures near absolute zero. Two vertical lasers are used to gently toss the ball upward (the "fountain" action), and then all of the lasers are turned off.

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Laser-Cooled Atoms: Cesium – Uncertain Principles Archive

Laser-Cooled Atoms: Cesium. Posted on September 3, 2013 by Chad Orzel. Element: Cesium (Cs) Atomic Number: 55. Mass: One stable isotope, mass 133 amu. Laser cooling wavelength: 854nm, but see below. Doppler cooling limit: 125 μK. Chemical classification: Yet another alkali metal, column I of the periodic table. This one isn't greyish, though!

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Ion microscopy based on laser-cooled cesium atoms

Efficient atomic ionization is obtained by laser promoting ground-state atoms into a target excited … We demonstrate a prototype of a Focused Ion Beam machine based on the ionization of a laser-cooled cesium beam and adapted for imaging and modifying different surfaces in the few-tens nanometer range. Efficient atomic ionization is obtained ...

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Temperature Measurements of Laser Cooled Cesium Atoms

Abstract. Cesium atoms in optical molasses have been laser cooled to a temperature of 70 µK ± 40 µK. The observed temperature and its variation with laser power and detuning are in strong disagreement with the conventional laser cooling theory. We present the experimental results and we give a tentative explanation for these anomalously low ...

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A cold cesium atomic beam produced out of a pyramidal funnel

Conclusions. We have built a cesium atomic beam, exploiting a pyramidal funnel. The atomic flux, as derived by the absorption and longitudinal velocity data and assuming a circular space distribution, (diameter 1.8 mm, see Section 4) is 4×10 9 atoms / s (at a longitudinal velocity of 10 m/s) and the longitudinal velocity is v z =8–12 m / s ...

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A laser cooled cesium atomic fountain: towards a high

The authors report the first realization of Zacharias's proposal for observing a Ramsey resonance in an atomic fountain. With presently achieved atom density and temperature, one envisions cold cesium fountain clocks with unprecedented performances both in stability (10 -16 /day) and accuracy (10 -16 ).

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ISS: ACES / PHARAO

PHARAO -a laser-cooled cesium atomic clock. PHARAO, which has been developed by CNES in collaboration with the laboratories SYRTE and LKB in Paris, France, is the first primary frequency standard specially designed for operation in space. PHARAO is the main instrument of the ESA mission ACES (Atomic Clock Ensemble in Space).

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Laser-Cooled Atoms: Cesium – Uncertain Principles Archive - Chad …

Happily, cesium has a laser cooling transition in the near infrared, at 854 nm, which is a relatively convenient laser wavelength. And, indeed, the best primary clocks in the world are now laser-cooled fountain clocks; the first came on-line in Paris in the 1990's, and all the major national standards labs have fountains these days.

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Device for Generating a Low Temperature, Highly Ionized …

A device for generating a linear, highly ionized, low temperature cesium plasma is described. The plasma is generated by having the output of cesium atomic beam ovens impinge on hot tungsten plates placed at both ends of a cylindrical vacuum chamber. The walls of the chamber are cooled so that neutral cesium condenses on them.

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Transverse cooling of a cesium atomic beam — Korea University

We cooled the transverse motion of a cesium atomic beam from an oven by using a blue-detuned standing wave. We employed a Fabry-Perot interferometer with a pair of flat mirrors to produce a standing wave with a beam diameter of 1 cm and an intracavity intensity of 3.2 W/cm 2.We analyzed the change in the fluorescence spectra of the tilted atomic beam with and …

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Cooling of cesium atomic beam with light from spectrally …

cesium atom is also shown. circularly polarized laser beams from two diode lasers (Spectra Diode Laboratories Model SDL-5420) are colli-mated to overlap the cesium beam over its entire length. The two laser beams propagate opposite to the atomic beam. A weak uniform magnetic field of a few gauss is applied over the entire length of the atomic ...

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[1812.02887] Laser-cooled caesium atoms confined with magic-wavelength ...

Download PDF Abstract: We report loading of laser-cooled caesium atoms into a hollow-core photonic-bandgap fiber and confining the atoms in the fiber's 7 $mu m$ diameter core with a magic-wavelength dipole trap at $sim$935 nm. The use of the magic wavelength removes the AC-Stark shift of the 852nm optical transition in caesium caused by the dipole …

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Ion microscopy based on laser-cooled cesium atoms - PubMed

Efficient atomic ionization is obtained by laser promoting ground-state atoms into a target excited … We demonstrate a prototype of a Focused Ion Beam machine based on the ionization of a laser-cooled cesium beam and adapted for imaging and modifying different surfaces in the few-tens nanometer range. Efficient atomic ionization is obtained ...

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PARCS: NASA's laser-cooled atomic clock in space

The PARCS cesium physics package (Heavner et al., 2001), shown in Fig. 2, includes a source region where atoms are gathered as optical molasses and launched; a 75-cm long Ramsey microwave cavity (Dick et al., 2003); and a detection region where the states of the arriving atoms are determined using optical methods.A key feature of the PARCS design is the …

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Cesium (Cs) - Chemical properties, Health and Environmental effects

Cesium is used in atomic clocks and more recently in ion propulsion systems. Cesium in the environment. Although cesium is much less abundant than the other alkali metals, it is still more common than elements like arsenic, iodine and uranium. Few cesium mineral are know, pollucite is the main: they are silicate magmas cooled from granites.

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Ion microscopy based on laser-cooled cesium atoms

An intense effusive atomic beam is transversely cooled using laser cooling techniques. Electrons or ions (depending on electrode polarities) are produced either by laser excitation to Rydberg states that are then field-ionized or by photo-ionization. The laser apparatus, the optical setup and the FIB column are not shown in the picture.

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