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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Observation of picosecond superfluorescent pulses in rubidium atomic vapor pumped by 100-fs laser pulses  

E-Print Network [OSTI]

We study the superfluorescence (SF) from a gas of rubidium atoms. The atoms of a dense vapor are excited to the 5D state from the 5S state by a two-photon process driven by 100-fs laser pulses. The atoms decay to the 6P state and then to the 5S...

Ariunbold, Gombojav O.; Kash, Michael M.; Sautenkov, Vladimir A.; Li, Hebin; Rostovtsev, Yuri V.; Welch, George R.; Scully, Marlan O.

2010-01-01T23:59:59.000Z

2

E-Print Network 3.0 - atomic vapor laser Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

with the exception of pagination. IEEE TRANSACTIONS ON PLASMA SCIENCE 1 Summary: vapor, atomic physics and vapor ionization, absorption reflection in a heated plasma layer, and...

3

Atomic vapor laser isotope separation of lead-210 isotope  

DOE Patents [OSTI]

An isotopically selective laser process and apparatus for removal of Pb-210 from natural lead that involves a one-photon near-resonant, two-photon resonant excitation of one or more Rydberg levels, followed by field ionization and then electrostatic extraction. The wavelength to the near-resonant intermediate state is counter propagated with respect to the second wavelength required to populate the final Rydberg state. This scheme takes advantage of the large first excited state cross section, and only modest laser fluences are required. The non-resonant process helps to avoid two problems: first, stimulated Raman Gain due to the nearby F=3/2 hyperfine component of Pb-207 and, second, direct absorption of the first transition process light by Pb-207.

Scheibner, Karl F. (Tracy, CA); Haynam, Christopher A. (Pleasanton, CA); Johnson, Michael A. (Pleasanton, CA); Worden, Earl F. (Diablo, CA)

1999-01-01T23:59:59.000Z

4

Atomic vapor laser isotope separation of lead-210 isotope  

DOE Patents [OSTI]

An isotopically selective laser process and apparatus for removal of Pb-210 from natural lead that involves a one-photon near-resonant, two-photon resonant excitation of one or more Rydberg levels, followed by field ionization and then electrostatic extraction. The wavelength to the near-resonant intermediate state is counter propagated with respect to the second wavelength required to populate the final Rydberg state. This scheme takes advantage of the large first excited state cross section, and only modest laser fluences are required. The non-resonant process helps to avoid two problems: first, stimulated Raman Gain due to the nearby F=3/2 hyperfine component of Pb-207 and, second, direct absorption of the first transition process light by Pb-207. 5 figs.

Scheibner, K.F.; Haynam, C.A.; Johnson, M.A.; Worden, E.F.

1999-08-31T23:59:59.000Z

5

Detection of slow atoms confined in a Cesium vapor cell by spatially separated pump and probe laser beams  

E-Print Network [OSTI]

Detection of slow atoms confined in a Cesium vapor cell by spatially separated pump and probe laser distribution of atoms in a thermal gas is usually described through a Maxwell-Boltzman distribution of energy, and assumes isotropy. As a consequence, the probability for an atom to leave the surface under an azimuth

Boyer, Edmond

6

Diode-laser-based atomic absorption monitor using frequency-modulation spectroscopy for physical vapor deposition process control  

E-Print Network [OSTI]

Diode-laser-based atomic absorption monitor using frequency-modulation spectroscopy for physical, and the dynamic events occur- ring as vapors condense on a substrate. Atomic absorption AA spectroscopy also been measured by means of the Doppler frequency shifts of the atomic absorption with respect

Fejer, Martin M.

7

Observation of picosecond superfluorescent pulses in rubidium atomic vapor pumped by 100-fs laser pulses  

SciTech Connect (OSTI)

We study the superfluorescence (SF) from a gas of rubidium atoms. The atoms of a dense vapor are excited to the 5D state from the 5S state by a two-photon process driven by 100-fs laser pulses. The atoms decay to the 6P state and then to the 5S state. The SF emission at 420 nm on the 6P-5S transition is recorded by a streak camera with picosecond time resolution. The time duration of the generated SF is tens of picoseconds, which is much shorter than the time scale of the usual relaxation processes, including spontaneous emission and atomic coherence dephasing. The dependence of the time delay between the reference input pulse and SF is measured as a function of laser power. The experimental data are described quantitatively by a simulation based on the semiclassical atom-field interaction theory. The observed change in scaling laws for the peak intensity and delay time can be elucidated by an SF theory in which the sample length is larger than the cooperation length.

Ariunbold, Gombojav O. [Institute for Quantum Studies and Department of Physics, Texas A and M University, College Station, Texas 77843 (United States); Department of Physics, National University of Mongolia, 210646 Ulaanbaatar (Mongolia); Kash, Michael M. [Institute for Quantum Studies and Department of Physics, Texas A and M University, College Station, Texas 77843 (United States); Department of Physics, Lake Forest College, Lake Forest, Illinois 60045 (United States); Sautenkov, Vladimir A. [Institute for Quantum Studies and Department of Physics, Texas A and M University, College Station, Texas 77843 (United States); Lebedev Institute of Physics, Moscow 119991 (Russian Federation); Li, Hebin; Welch, George R. [Institute for Quantum Studies and Department of Physics, Texas A and M University, College Station, Texas 77843 (United States); Rostovtsev, Yuri V. [Institute for Quantum Studies and Department of Physics, Texas A and M University, College Station, Texas 77843 (United States); Department of Physics, University of North Texas, 1155 Union Circle 311427, Denton, Texas 76203 (United States); Scully, Marlan O. [Institute for Quantum Studies and Department of Physics, Texas A and M University, College Station, Texas 77843 (United States); Applied Physics and Materials Science Group, Princeton University, Princeton, New Jersey 08544 (United States); Max-Planck-Institute fuer Quantenoptik, D-85748 Garching (Germany)

2010-10-15T23:59:59.000Z

8

Application of atomic vapor laser isotope separation to the enrichment of mercury  

SciTech Connect (OSTI)

Workers at GTE/Sylvania have shown that the efficiency of fluorescent lighting may be markedly improved using mercury that has been enriched in the /sup 196/Hg isotope. A 5% improvement in the efficiency of fluorescent lighting in the United States could provide a savings of approx. 1 billion dollars in the corresponding reduction of electrical power consumption. We will discuss the results of recent work done at our laboratory to develop a process for enriching mercury. The discussion will center around the results of spectroscopic measurements of excited state lifetimes, photoionization cross sections and isotope shifts. In addition, we will discuss the mercury separator and supporting laser mesurements of the flow properties of mercury vapor. We will describe the laser system which will provide the photoionization and finally discuss the economic details of producing enriched mercury at a cost that would be attractive to the lighting industry.

Crane, J.K.; Erbert, G.V.; Paisner, J.A.; Chen, H.L.; Chiba, Z.; Beeler, R.G.; Combs, R.; Mostek, S.D.

1986-09-01T23:59:59.000Z

9

Laser-induced fluorescence measurements and kinetic analysis of Si atom formation in a rotating disk chemical vapor deposition reactor  

SciTech Connect (OSTI)

An extensive set of laser-induced fluorescence (LIF) measurements of Si atoms during the chemical vapor deposition (CVD) of silicon from silane and disilane in a research rotating disk reactor are presented. The experimental results are compared in detail with predictions from a numerical model of CVD from silane and disilane that treats the fluid flow coupled to gas-phase and gas-surface chemistry. The comparisons showed that the unimolecular decomposition of SiH[sub 2] could not account for the observed gas-phase Si atom density profiles. The H[sub 3]SiSiH [leftrightarrow] Si + SiH[sub 4] and H[sub 3]SiSiH + SiH[sub 2] [leftrightarrow] Si + Si[sub 2]H[sub 6] reactions are proposed as the primary Si atom production routes. The model is in good agreement with the measured shapes of the Si atom profiles and the trends in Si atom density with susceptor temperature, pressure, and reactant gas mixture. 33 refs., 12 figs., 3 tabs.

Ho, P.; Coltrin, M.E.; Breiland, W.G. (Sandia National Lab., Albuquerque, NM (United States))

1994-10-06T23:59:59.000Z

10

Atomic vapor laser isotope separation at Lawrence Livermore National Laboratory: a status report  

SciTech Connect (OSTI)

The field of laser induced chemistry began in earnest early in the 1970's with the initiation of major efforts in laser isotope separation (LIS) of uranium. Though many specialized, small-scale photochemical and diagnostic applications have been identified and evaluated experimentally, and continue to show promise, currently the only high payoff, large-scale applications remain LIS of special elements. Aspects of the physical scaling, technology status and economic basis of uranium LIS are examined with special emphasis on the effort at LLNL.

Davis, J.I.

1980-01-01T23:59:59.000Z

11

Coherent Control of Laser Field and Spectroscopy in Dense Atomic Vapor  

E-Print Network [OSTI]

-optic modulator; AOM - acousto-optic modulator; PD - photodiode; the oven is assembled with 1. copper tube; 2. non-magnetic heater; 3. magnetic shield; 4. microwave cavity with antenna; 5. Rb cell. Inset (a) shows the relative frequency of the laser fields. L1...

Li, Hebin

2011-08-08T23:59:59.000Z

12

Wick for metal vapor laser  

DOE Patents [OSTI]

An improved wick for a metal vapor laser is made of a refractory metal cylinder, preferably molybdenum or tungsten for a copper laser, which provides the wicking surface. Alternately, the inside surface of the ceramic laser tube can be metalized to form the wicking surface. Capillary action is enhanced by using wire screen, porous foam metal, or grooved surfaces. Graphite or carbon, in the form of chunks, strips, fibers or particles, is placed on the inside surface of the wick to reduce water, reduce metal oxides and form metal carbides.

Duncan, David B. (Livermore, CA)

1992-01-01T23:59:59.000Z

13

Copper vapor laser modular packaging assembly  

DOE Patents [OSTI]

A modularized packaging arrangement for one or more copper vapor lasers and associated equipment is disclosed herein. This arrangement includes a single housing which contains the laser or lasers and all their associated equipment except power, water and neon, and means for bringing power, water, and neon which are necessary to the operation of the lasers into the container for use by the laser or lasers and their associated equipment.

Alger, Terry W. (Tracy, CA); Ault, Earl R. (Dublin, CA); Moses, Edward I. (Castro Valley, CA)

1992-01-01T23:59:59.000Z

14

VOLUME 6S, NUMBER 13 PHYSICAL REVIEW LETTERS Very Cold Trapped Atoms in a Vapor Cell  

E-Print Network [OSTI]

VOLUME 6S, NUMBER 13 PHYSICAL REVIEW LETTERS Very Cold Trapped Atoms in a Vapor Cell 24 SEPTEMBER sample of spin-polarized trapped atoms. The technique used dramati- cally simplifies the production of laser-cooled atoms. In this experiment, 1.8x10' neutral cesium atoms were optically captured directly

Monroe, Christopher

15

Diode pumped alkali vapor fiber laser  

DOE Patents [OSTI]

A method and apparatus is provided for producing near-diffraction-limited laser light, or amplifying near-diffraction-limited light, in diode pumped alkali vapor photonic-band-gap fiber lasers or amplifiers. Laser light is both substantially generated and propagated in an alkali gas instead of a solid, allowing the nonlinear and damage limitations of conventional solid core fibers to be circumvented. Alkali vapor is introduced into the center hole of a photonic-band-gap fiber, which can then be pumped with light from a pump laser and operated as an oscillator with a seed beam, or can be configured as an amplifier.

Payne, Stephen A. (Castro Valley, CA); Beach, Raymond J. (Livermore, CA); Dawson, Jay W. (Livermore, CA); Krupke, William F. (Pleasanton, CA)

2006-07-26T23:59:59.000Z

16

Diode pumped alkali vapor fiber laser  

DOE Patents [OSTI]

A method and apparatus is provided for producing near-diffraction-limited laser light, or amplifying near-diffraction-limited light, in diode pumped alkali vapor photonic-band-gap fiber lasers or amplifiers. Laser light is both substantially generated and propagated in an alkali gas instead of a solid, allowing the nonlinear and damage limitations of conventional solid core fibers to be circumvented. Alkali vapor is introduced into the center hole of a photonic-band-gap fiber, which can then be pumped with light from a pump laser and operated as an oscillator with a seed beam, or can be configured as an amplifier.

Payne, Stephen A. (Castro Valley, CA); Beach, Raymond J. (Livermore, CA); Dawson, Jay W. (Livermore, CA); Krupke, William F. (Pleasanton, CA)

2007-10-23T23:59:59.000Z

17

Storing images in warm atomic vapor  

E-Print Network [OSTI]

Reversible and coherent storage of light in atomic medium is a key-stone of future quantum information applications. In this work, arbitrary two-dimensional images are slowed and stored in warm atomic vapor for up to 30 $\\mu$s, utilizing electromagnetically induced transparency. Both the intensity and the phase patterns of the optical field are maintained. The main limitation on the storage resolution and duration is found to be the diffusion of atoms. A techniqueanalogous to phase-shift lithography is employed to diminish the effect of diffusion on the visibility of the reconstructed image.

M. Shuker; O. Firstenberg; R. Pugatch; A. Ron; N. Davidson

2008-06-17T23:59:59.000Z

18

Energy balance in laser-irradiated vaporizing droplets  

Science Journals Connector (OSTI)

The interactions of vaporizing aerosols with a high energy laser beam are analyzed in the diffusive vaporization regime. This is the regime in which diffusive mass transport and...

Zardecki, Andrew; Armstrong, Robert L

1988-01-01T23:59:59.000Z

19

Process for producing enriched uranium having a {sup 235}U content of at least 4 wt. % via combination of a gaseous diffusion process and an atomic vapor laser isotope separation process to eliminate uranium hexafluoride tails storage  

DOE Patents [OSTI]

An uranium enrichment process capable of producing an enriched uranium, having a {sup 235}U content greater than about 4 wt. %, is disclosed which will consume less energy and produce metallic uranium tails having a lower {sup 235}U content than the tails normally produced in a gaseous diffusion separation process and, therefore, eliminate UF{sub 6} tails storage and sharply reduce fluorine use. The uranium enrichment process comprises feeding metallic uranium into an atomic vapor laser isotope separation process to produce an enriched metallic uranium isotopic mixture having a {sup 235} U content of at least about 2 wt. % and a metallic uranium residue containing from about 0.1 wt. % to about 0.2 wt. % {sup 235} U; fluorinating this enriched metallic uranium isotopic mixture to form UF{sub 6}; processing the resultant isotopic mixture of UF{sub 6} in a gaseous diffusion process to produce a final enriched uranium product having a {sup 235}U content of at least 4 wt. %, and up to 93.5 wt. % or higher, of the total uranium content of the product, and a low {sup 235}U content UF{sub 6} having a {sup 235}U content of about 0.71 wt. % of the total uranium content of the low {sup 235}U content UF{sub 6}; and converting this low {sup 235}U content UF{sub 6} to metallic uranium for recycle to the atomic vapor laser isotope separation process. 4 figs.

Horton, J.A.; Hayden, H.W. Jr.

1995-05-30T23:59:59.000Z

20

Process for producing enriched uranium having a .sup.235 U content of at least 4 wt. % via combination of a gaseous diffusion process and an atomic vapor laser isotope separation process to eliminate uranium hexafluoride tails storage  

DOE Patents [OSTI]

An uranium enrichment process capable of producing an enriched uranium, having a .sup.235 U content greater than about 4 wt. %, is disclosed which will consume less energy and produce metallic uranium tails having a lower .sup.235 U content than the tails normally produced in a gaseous diffusion separation process and, therefore, eliminate UF.sub.6 tails storage and sharply reduce fluorine use. The uranium enrichment process comprises feeding metallic uranium into an atomic vapor laser isotope separation process to produce an enriched metallic uranium isotopic mixture having a .sup.235 U content of at least about 2 wt. % and a metallic uranium residue containing from about 0.1 wt. % to about 0.2 wt. % .sup.235 U; fluorinating this enriched metallic uranium isotopic mixture to form UF.sub.6 ; processing the resultant isotopic mixture of UF.sub.6 in a gaseous diffusion process to produce a final enriched uranium product having a .sup.235 U content of at least 4 wt. %, and up to 93.5 wt. % or higher, of the total uranium content of the product, and a low .sup.235 U content UF.sub.6 having a .sup.235 U content of about 0.71 wt. % of the total uranium content of the low .sup.235 U content UF.sub.6 ; and converting this low .sup.235 U content UF.sub.6 to metallic uranium for recycle to the atomic vapor laser isotope separation process.

Horton, James A. (Livermore, CA); Hayden, Jr., Howard W. (Oakridge, TN)

1995-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Precision micro drilling with copper vapor lasers  

SciTech Connect (OSTI)

The authors have developed a copper vapor laser based micro machining system using advanced beam quality control and precision wavefront tilting technologies. Micro drilling has been demonstrated through percussion drilling and trepanning using this system. With a 30 W copper vapor laser running at multi-kHz pulse repetition frequency, straight parallel holes with size varying from 500 microns to less than 25 microns and with aspect ratio up to 1:40 have been consistently drilled on a variety of metals with good quality. For precision trepanned holes, the hole-to-hole size variation is typically within 1% of its diameter. Hole entrance and exit are both well defined with dimension error less than a few microns. Materialography of sectioned holes shows little (sub-micron scale) recast layer and heat affected zone with surface roughness within 1--2 microns.

Chang, J.J.; Martinez, M.W.; Warner, B.E.; Dragon, E.P.; Huete, G.; Solarski, M.E.

1994-09-02T23:59:59.000Z

22

Injection locked oscillator system for pulsed metal vapor lasers  

DOE Patents [OSTI]

An injection locked oscillator system for pulsed metal vapor lasers is disclosed. The invention includes the combination of a seeding oscillator with an injection locked oscillator (ILO) for improving the quality, particularly the intensity, of an output laser beam pulse. The present invention includes means for matching the first seeder laser pulses from the seeding oscillator to second laser pulses of a metal vapor laser to improve the quality, and particularly the intensity, of the output laser beam pulse.

Warner, Bruce E. (Livermore, CA); Ault, Earl R. (Dublin, CA)

1988-01-01T23:59:59.000Z

23

E-Print Network 3.0 - atom vapor cells Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

rotation in the vapor cell due to inten- sity-induced birefringence in the rubidium atomic vapor. While... Super efficient absorption filter for quantum memory using atomic...

24

Self-tuning method for monitoring the density of a gas vapor component using a tunable laser  

DOE Patents [OSTI]

The present invention relates to a vapor density monitor and laser atomic absorption spectroscopy method for highly accurate, continuous monitoring of vapor densities, composition, flow velocity, internal and kinetic temperatures and constituent distributions. The vapor density monitor employs a diode laser, preferably of an external cavity design. By using a diode laser, the vapor density monitor is significantly less expensive and more reliable than prior art vapor density monitoring devices. In addition, the compact size of diode lasers enables the vapor density monitor to be portable. According to the method of the present invention, the density of a component of a gas vapor is calculated by tuning the diode laser to a frequency at which the amount of light absorbed by the component is at a minimum or a maximum within about 50 MHz of that frequency. Laser light from the diode laser is then transmitted at the determined frequency across a predetermined pathlength of the gas vapor. By comparing the amount of light transmitted by the diode laser to the amount of light transmitted after the laser light passes through the gas vapor, the density of the component can be determined using Beer's law.

Hagans, Karla (Livermore, CA); Berzins, Leon (Livermore, CA); Galkowski, Joseph (Livermore, CA); Seng, Rita (Tracy, CA)

1996-01-01T23:59:59.000Z

25

Self-tuning method for monitoring the density of a gas vapor component using a tunable laser  

DOE Patents [OSTI]

The present invention relates to a vapor density monitor and laser atomic absorption spectroscopy method for highly accurate, continuous monitoring of vapor densities, composition, flow velocity, internal and kinetic temperatures and constituent distributions. The vapor density monitor employs a diode laser, preferably of an external cavity design. By using a diode laser, the vapor density monitor is significantly less expensive and more reliable than prior art vapor density monitoring devices. In addition, the compact size of diode lasers enables the vapor density monitor to be portable. According to the method of the present invention, the density of a component of a gas vapor is calculated by tuning the diode laser to a frequency at which the amount of light absorbed by the component is at a minimum or a maximum within about 50 MHz of that frequency. Laser light from the diode laser is then transmitted at the determined frequency across a predetermined pathlength of the gas vapor. By comparing the amount of light transmitted by the diode laser to the amount of light transmitted after the laser light passes through the gas vapor, the density of the component can be determined using Beer`s law. 6 figs.

Hagans, K.; Berzins, L.; Galkowski, J.; Seng, R.

1996-08-27T23:59:59.000Z

26

Laser techniques for studying chemical vapor deposition  

SciTech Connect (OSTI)

Chemical vapor deposition (CVD) is widely used to produce thin films for microelectronics, protective coatings and other materials processing applications. Despite the large number of applications, however, little is known about the fundamental chemistry and physics of most CVD processes. CVD recipes have generally been determined empirically, but as process requirements become more stringent, a more basic understanding will be needed to improve reactor design and speed process optimization. In situ measurements of the reacting gas are important steps toward gaining such an understanding, both from the standpoint of characterizing the reactor and testing models of a CVD process. Our work, a coordinated program of experimental and theoretical research in the fundamental mechanisms of CVD, illustrates the application of laser techniques to the understanding of a CVD system. We have used a number of laser-based techniques to probe CVD systems and have compared our measurements with predictions from computer models, primarily for the silane CVD system. The silane CVD model solves the two-dimensional, steady-state boundary layer equations of fluid flow coupled to 26 elementary chemical reactions describing the thermal decomposition of silane and the subsequent reactions of intermediate species that result in the deposition of a silicon film.

Ho, P.; Breiland, W.G.; Coltrin, M.E.

1990-01-01T23:59:59.000Z

27

Gas-phase silicon atom densities in the chemical vapor deposition of silicon from silane  

SciTech Connect (OSTI)

Silicon atom number density profiles have been measured using laser-induced fluorescence during the chemical vapor deposition of silicon from silane. Measurements were obtained in a rotating-disk reactor as a function of silane partial pressure and the amount of hydrogen added to the carrier gas. Absolute number densities were obtained using an atomic absorption technique. Results were compared with calculated density profiles from a model of the coupled fluid flow, gas-phase and surface chemistry for an infinite-radius rotating disk. An analysis of the reaction mechanism showed that the unimolecular decomposition of SiH{sub 2} is not the dominant source of Si atoms. Profile shapes and positions, and all experimental trends are well matched by the calculations. However, the calculated number density is up to 100 times smaller than measured.

Coltrin, M.E.; Breiland, W.G.; Ho, P.

1993-12-31T23:59:59.000Z

28

High average power magnetic modulator for metal vapor lasers  

DOE Patents [OSTI]

A three-stage magnetic modulator utilizing magnetic pulse compression designed to provide a 60 kV pulse to a copper vapor laser at a 4.5 kHz repetition rate is disclosed. This modulator operates at 34 kW input power. The circuit includes a step up auto transformer and utilizes a rod and plate stack construction technique to achieve a high packing factor.

Ball, Don G. (Livermore, CA); Birx, Daniel L. (Oakley, CA); Cook, Edward G. (Livermore, CA); Miller, John L. (Livermore, CA)

1994-01-01T23:59:59.000Z

29

Conservation laws and laser cooling of atoms  

E-Print Network [OSTI]

The straightforward application of energy and linear momentum conservation to the absorption/emission of photons by atoms--first outlined by Schr\\"odinger in 1922--allows to establish the essential features of laser cooling of two levels atoms at low laser intensities. The minimum attainable average kinetic energy of the atoms depends on the ratio $\\Gamma/E_R$ between the natural linewidth and the recoil energy and tends to $E_R$ as $\\Gamma/E_R$ tends to zero. This treatment is valid for any value of the ratio $\\Gamma/E_R$ and contains the semiclassical theory of laser cooling as the limiting case in which $E_R\\ll \\Gamma$.

Giuliani, Giuseppe

2015-01-01T23:59:59.000Z

30

Channelization architecture for wide-band slow light in atomic vapors  

E-Print Network [OSTI]

We propose a ``channelization'' architecture to achieve wide-band electromagnetically induced transparency (EIT) and ultra-slow light propagation in atomic Rb-87 vapors. EIT and slow light are achieved by shining a strong, resonant ``pump'' laser on the atomic medium, which allows slow and unattenuated propagation of a weaker ``signal'' beam, but only when a two-photon resonance condition is satisfied. Our wideband architecture is accomplished by dispersing a wideband signal spatially, transverse to the propagation direction, prior to entering the atomic cell. When particular Zeeman sub-levels are used in the EIT system, then one can introduce a magnetic field with a linear gradient such that the two-photon resonance condition is satisfied for each individual frequency component. Because slow light is a group velocity effect, utilizing differential phase shifts across the spectrum of a light pulse, one must then introduce a slight mismatch from perfect resonance to induce a delay. We present a model which accounts for diffusion of the atoms in the varying magnetic field as well as interaction with levels outside the ideal three-level system on which EIT is based. We find the maximum delay-bandwidth product decreases with bandwidth, and that delay-bandwidth product ~1 should be achievable with bandwidth ~50 MHz (~5 ns delay). This is a large improvement over the ~1 MHz bandwidths in conventional slow light systems and could be of use in signal processing applications.

Zachary Dutton; Mark Bashkansky; Michael Steiner; John Reintjes

2005-10-20T23:59:59.000Z

31

Subnanosecond photodissociation atomic iodine laser  

SciTech Connect (OSTI)

The Q factor of an iodine photodissociation laser was switched periodically by a quarter-wave Pockels cell. The voltage applied to the cell was produced by discharging a cable line and it represented a sequence of damped trapezoidal pulses with steep edges. The repetition period of the transmission maxima of the switch was equal to the round-trip time of the resonator. The gas mixture consisted of C/sub 3/F/sub 7/I (7--15 Torr) and Ar; the total pressure was 1 atm. A train of subnanosecond laser pulses consisting of 3--4 pulses was obtained. The total energy of the train was 10--20 mJ and the minimum duration of a single pulse was 0.4 nsec.

Acnenkov, V.I.; Belotserkovets, A.V.; Grigorovich, S.V.

1981-09-01T23:59:59.000Z

32

Atomic flux measurement by diode-laser-based atomic absorption spectroscopy  

E-Print Network [OSTI]

Atomic flux measurement by diode-laser-based atomic absorption spectroscopy Weizhi Wang,a) R. H, California 94305 Received 5 May 1999; accepted 6 June 1999 Diode-laser-based atomic absorption AA sensors- quirements, and only the QCM measures the flux. Lamp- based atomic absorption AA sensors have been success

Fejer, Martin M.

33

Atom interferometric gravitational wave detection using heterodyne laser links  

E-Print Network [OSTI]

We propose a scheme based on a heterodyne laser link that allows for long baseline gravitational wave detection using atom interferometry. While the baseline length in previous atom-based proposals is constrained by the need for a reference laser to remain collimated as it propagates between two satellites, here we circumvent this requirement by employing a strong local oscillator laser near each atom ensemble that is phase locked to the reference laser beam. Longer baselines offer a number of potential advantages, including enhanced sensitivity, simplified atom optics, and reduced atomic source flux requirements.

Hogan, Jason M

2015-01-01T23:59:59.000Z

34

CO-CATALYTIC ABSORPTION LAYERS FOR CONTROLLED LASER-INDUCED CHEMICAL VAPOR DEPOSITION OF CARBON NANOTUBES  

E-Print Network [OSTI]

The concept of co-catalytic layer structures for controlled laser-induced chemical vapor deposition of carbon nanotubes is established, in which a thin Ta support layer chemically aids the initial Fe catalyst reduction. This enables a significant...

Michaelis, F.B.; Weatherup, R.S.; Bayer, B.C.; Bock, M.C.D; Sugime, H.; Caneva, S.; Robertson, J.; Baumberg, J.J.; Hofmann, S.

2014-02-24T23:59:59.000Z

35

Assessment of soot particle vaporization effects during laser-induced incandescence with  

E-Print Network [OSTI]

Assessment of soot particle vaporization effects during laser-induced incandescence with time-induced incandescence (LII) has been successfully used for soot volume fraction and particle size measurements

Hahn, David W.

36

Laser vaporization/ionization interface for coupling microscale separation techniques with mass spectrometry  

DOE Patents [OSTI]

The present invention provides a laser-induced vaporization and ionization interface for directly coupling microscale separation processes to a mass spectrometer. Vaporization and ionization of the separated analytes are facilitated by the addition of a light-absorbing component to the separation buffer or solvent. 8 figs.

Yeung, E.S.; Chang, Y.C.

1999-06-29T23:59:59.000Z

37

Nonresonant femtosecond laser vaporization of aqueous protein preserves folded structure  

Science Journals Connector (OSTI)

...molecules and ions in strong laser fields . Phys Rev A 68 : 011402...generated by ultra-intense lasers . Science 300 : 1107 – 1111 . 10 Ditmire T ( 1999 ) Nuclear fusion from explosions of femtosecond laser-heated deuterium clusters . Nature...

John J. Brady; Elizabeth J. Judge; Robert J. Levis

2011-01-01T23:59:59.000Z

38

Measurement of Water Vapor Concentration using Tunable Diode Laser Absorption Spectroscopy  

E-Print Network [OSTI]

Tunable diode laser spectroscopy and the Beer-Lambert relation has been used to measure the absorption of water vapor both in an absorption cell and in a shock tube. The purpose of this thesis is to develop a laser diagnostic capable of determining...

Barrett, Alexander B.

2010-07-14T23:59:59.000Z

39

Cooling and Trapping Atoms Atoms are slowed and cooled by radiation pressure from laser light  

E-Print Network [OSTI]

Cooling and Trapping Atoms Atoms are slowed and cooled by radiation pressure from laser light and then trapped in a bottle whose "walls" are magnetic fields. Cooled atoms are ideal for exploring basic. research has traditionally been the study of the intrinsic prop erties of isolated atoms. In the early part

Johannesson, Henrik

40

An atomic-scale analysis of catalytically-assisted chemical vapor deposition of carbon nanotubes  

E-Print Network [OSTI]

An atomic-scale analysis of catalytically-assisted chemical vapor deposition of carbon nanotubes M Growth of carbon nanotubes during transition-metal particles catalytically-assisted thermal decomposition of various nanotube surface and edge reactions (e.g. adsorption of hydrocarbons and hydrogen onto the surface

Grujicic, Mica

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Laser-Ranging Long Baseline Differential Atom Interferometers for Space  

E-Print Network [OSTI]

High sensitivity differential atom interferometers are promising for precision measurements in science frontiers in space, including gravity field mapping for Earth science studies and gravitational wave detection. We propose a new configuration of twin atom interferometers connected by a laser ranging interferometer (LRI-AI) to provide precise information of the displacements between the two AI reference mirrors and a means to phase-lock the two independent interferometer lasers over long distances, thereby further enhancing the feasibility of long baseline differential atom interferometers. We show that a properly implemented LRI-AI can achieve equivalent functionality to the conventional differential atom interferometer measurement system. LRI-AI isolates the laser requirements for atom interferometers and for optical phase readout between distant locations, thus enabling optimized allocation of available laser power within a limited physical size and resource budget. A unique aspect of LRI-AI also enables...

Chiow, Sheng-wey; Yu, Nan

2015-01-01T23:59:59.000Z

42

Laser-induced "two-atom" coherence  

Science Journals Connector (OSTI)

Our analysis shows that if an electromagnetic field excites a coherent superposition of states of two different types of atoms, then the results of a collision of those two atoms can be quite different from the usual dephasing that a coherently excited atom suffers upon collision with another atom. We present the concept of "two-atom" coherence as one feature of this interaction where the field of a given wavelength may interact with the system coherently over a wide range of internuclear distances.

Munir H. Nayfeh and G. B. Hillard

1984-04-01T23:59:59.000Z

43

A tunable MWIR laser remote sensor for chemical vapor detection  

Science Journals Connector (OSTI)

The Air Force vision for Global Virtual Presence suggests a need for active remote sensing systems that provide both global coverage and the ability to detect multiple gaseous chemical species at low concentration from a significant standoff distance. The system will need to have acceptable weight volume and power characteristics as well as a long operating lifetime for integration with various surveillance platforms. Laser based remote sensing systems utilizing the differential absorption lidar (DIAL) technique are promising for long range chemical sensing applications. Recent advancements in pulsed diode pumped solid state laser (DPSSL) technology and in tunable optical parametric oscillators (OPO) make broadly tunable laser transmitters possible for the DIAL system. Also the characteristic narrow spectral bandwidth of these laser devices provides high measurement sensitivity and spectral selectivity with the potential to avoid interfering species. Rocketdyne has built and tested a tunable midwave infrared (MWIR) DIAL system using DPSSL/OPO technology. The key to the system is a novel tuning and line narrowing technology developed for the OPO. The tuning system can quickly adjust to the desired wavelength and precisely locate a narrow spectral feature of interest. Once the spectral feature is located a rapid dither tuning technique is employed. The laser pulses are tuned “on” and “off” the spectral resonance of a molecule with precise and repeatable performance as required to make the DIAL measurement. To date the breadboard system has been tested by measuring methane ethane and sulfur dioxide in a calibrated gas cell at a range of 60 meters.

Thomas L. Bunn; Patricia M. Noblett; William D. Otting

1998-01-01T23:59:59.000Z

44

An output coupler for Bose condensed atoms The observations of BEC have stimulated interest in atom lasers, coherent sources of  

E-Print Network [OSTI]

An output coupler for Bose condensed atoms The observations of BEC have stimulated interest in atom lasers, coherent sources of atomic matter waves. The build-up of atoms in the ground state of a magnetic. We demonstrated a scheme for doing this with Bose condensed atoms [1]. A variable fraction of atoms

45

Transmission electron microscopy and Monte Carlo simulations of ordering in Au-Cu clusters produced in a laser vaporization source  

Science Journals Connector (OSTI)

Au-Cu bimetallic alloy clusters are produced in a laser vaporization source starting from Au-Cu alloy targets with different stoichiometric compositions. The clusters are deposited on two different substrates—amorphous carbon and crystalline MgO—and are characterized by electron diffraction and high-resolution electron microscopy. The experiments show that the overall chemical composition in the clusters is the same as the chemical composition of the target material; but the crystal structure of the Au-Cu alloy clusters differs from their known bulk crystal structure. Electron microscopy experiments provide evidence that no chemical ordering exists between Au and Cu atoms and that the clusters are solid solutions. Monte Carlo simulations using the second moment tight-binding approximation, however, predict Cu3Au clusters ordered in the core but with a disordered mantle. The possible origins of the differences between experiment and Monte Carlo simulations are discussed.

B. Pauwels; G. Van Tendeloo; E. Zhurkin; M. Hou; G. Verschoren; L. Theil Kuhn; W. Bouwen; P. Lievens

2001-03-27T23:59:59.000Z

46

A Theory of Laser Induced Nuclear Reaction in Single Atoms  

SciTech Connect (OSTI)

An 'electron-bridge' mechanism of nuclear reaction in an atom or ion by ultra-intense laser fields is presented. A preliminary estimate of the intensity dependence of the rate of disintegration reaction of deuteron nucleus in deuterium atom is made for 800 nm laser fields. For intensities below 5x10{sup 21} W/cm{sup 2}, the rate of disintegration by the 'electron-bridge' mechanism is found to be small, but it rises sharply and becomes large already for {approx_equal}10{sup 22} W/cm{sup 2}.

Faisal, F. H. M.; Donner, C. [Fakultaet fuer Physik, Universitaet Bielefeld, Postfach 100131, D-33501 Bielefeld (Germany)

2010-02-02T23:59:59.000Z

47

Laser-induced nonresonant nuclear excitation in muonic atoms  

E-Print Network [OSTI]

Coherent nuclear excitation in strongly laser-driven muonic atoms is calculated. The nuclear transition is caused by the time-dependent Coulomb field of the oscillating charge density of the bound muon. A closed-form analytical expression for electric multipole transitions is derived and applied to various isotopes; the excitation probabilities are in general very small. We compare the process with other nuclear excitation mechanisms through coupling with atomic shells and discuss the prospects to observe it in experiment.

A. Shahbaz; C. Müller; T. J. Buervenich; C. H. Keitel

2008-12-13T23:59:59.000Z

48

Injection locking of a high power ultraviolet laser diode for laser cooling of ytterbium atoms  

E-Print Network [OSTI]

We developed a high-power laser system at a wavelength of 399 nm for laser cooling of ytterbium atoms with ultraviolet laser diodes. The system is composed of an external cavity laser diode providing frequency stabilized output at a power of 40 mW and another laser diode for amplifying the laser power up to 220 mW by injection locking. The systematic method for optimization of our injection locking can also be applied to high power light sources at any other wavelengths. Our system, which does not depend on complex nonlinear frequency-doubling, has great importance for implementing transportable optical lattice clocks, and is also useful for investigations on condensed matter physics or quantum information processing using cold atoms.

Toshiyuki Hosoya; Martin Miranda; Ryotaro Inoue; Mikio Kozuma

2014-12-02T23:59:59.000Z

49

Kinetics of laser pulse vaporization of uranium dioxide by mass spectrometry  

SciTech Connect (OSTI)

Safety analyses of nuclear reactors require knowledge of the evaporation behavior of UO/sub 2/ at temperatures well above the melting point of 3140 K. In this study, rapid transient heating of a small spot on a UO/sub 2/ specimen was accomplished by a laser pulse, which generates a surface temperature excursion. This in turn vaporizes the target surface and the gas expands into vacuum. The surface temperature transient was monitored by a fast-response automatic optical pyrometer. The maximum surface temperatures investigated range from approx. 3700 K to approx. 4300 K. A computer program was developed to simulate the laser heating process and calculate the surface temperature evolution. The effect of the uncertainties of the high temperature material properties on the calculation was included in a sensitivity study for UO/sub 2/ vaporization. The measured surface temperatures were in satisfactory agreements.

Tsai, C.

1981-11-01T23:59:59.000Z

50

Rescattering effects in laser-assisted electron-atom bremsstrahlung  

E-Print Network [OSTI]

Rescattering effects in nonresonant spontaneous laser-assisted electron-atom bremsstrahlung (LABrS) are analyzed within the framework of time-dependent effective-range (TDER) theory. It is shown that high energy LABrS spectra exhibit rescattering plateau structures that are similar to those that are well-known in strong field laser-induced processes as well as those that have been predicted theoretically in laser-assisted collision processes. In the limit of a low-frequency laser field, an analytic description of LABrS is obtained from a rigorous quantum analysis of the exact TDER results for the LABrS amplitude. This amplitude is represented as a sum of factorized terms involving three factors, each having a clear physical meaning. The first two factors are the exact field-free amplitudes for electron-atom bremsstrahlung and for electron-atom scattering, and the third factor describes free electron motion in the laser field along a closed trajectory between the first (scattering) and second (rescattering) co...

Zheltukhin, A N; Frolov, M V; Manakov, N L; Starace, Anthony F

2015-01-01T23:59:59.000Z

51

Steven Chu: Laser Cooling and Trapping of Atoms  

Office of Scientific and Technical Information (OSTI)

Steven Chu Steven Chu Laser Cooling and Trapping of Atoms Resources with Additional Information · Interviews, Speeches, and Presentations · Patents Steven Chu Photo Credit: Lawrence Berkeley National Laboratory Roy Kaltschmidt, Photographer Steven Chu was appointed by President Barack Obama to be the 12th Secretary of Energy and served in this capacity until April 22, 2013. He was previously Director of Lawrence Berkeley National Laboratory (LBNL), Professor in the Physics Department at the University of California, Berkeley, and 'the Theodore and Frances Geballe Professor of Physics and Applied Physics at Stanford University. Professor Chu's research is in atomic physics, polymer and biophysics. His thesis and postdoctoral work at Berkeley ... was the observation of parity non-conservation in atomic transitions in 1978. This experiment was one of the earliest atomic physics confirmations of the Weinberg-Salam-Glashow theory that unifies the weak and electromagnetic forces.

52

Steven Chu: Laser Cooling and Trapping of Atoms  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Steven Chu Steven Chu Laser Cooling and Trapping of Atoms Resources with Additional Information · Interviews, Speeches, and Presentations · Patents Steven Chu Photo Credit: Lawrence Berkeley National Laboratory Roy Kaltschmidt, Photographer Steven Chu was appointed by President Barack Obama to be the 12th Secretary of Energy and served in this capacity until April 22, 2013. He was previously Director of Lawrence Berkeley National Laboratory (LBNL), Professor in the Physics Department at the University of California, Berkeley, and 'the Theodore and Frances Geballe Professor of Physics and Applied Physics at Stanford University. Professor Chu's research is in atomic physics, polymer and biophysics. His thesis and postdoctoral work at Berkeley ... was the observation of parity non-conservation in atomic transitions in 1978. This experiment was one of the earliest atomic physics confirmations of the Weinberg-Salam-Glashow theory that unifies the weak and electromagnetic forces.

53

Hyperfine Studies of Lithium Vapor using Saturated Absorption Spectroscopy  

E-Print Network [OSTI]

the frequency of a laser with respect to an atomic spectral feature.[20] As such, saturated absorptionHyperfine Studies of Lithium Vapor using Saturated Absorption Spectroscopy? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 3.3 Broadening Mechanisms . . . . . . . . . . . . . . . . . . . . . 15 3.4 Saturated Absorption

Cronin, Alex D.

54

Collision cross sections and equilibrium fractions of ions and atoms in metal vapor targets. Project progress report, June 1, 1979-May 31, 1980  

SciTech Connect (OSTI)

The objective of this program is to measure atomic collision cross sections and equilibrium fractions of ions and atoms in metal vapor targets. The goal is to obtain experimental information on atomic collision processes relevant to the Magnetic Fusion Energy Program. In particular, in connection with the development of double charge exchange D/sup -/ ion sources, we are measuring D/sup -/ formation cross sections in alkaline-earth metal vapor targets. During the period covered in this report we have measured electron transfer cross sections for 3-40 keV D/sup +/ ions and D/sup 0/ atoms in collision with calcium vapor.

Morgan, T J

1980-01-01T23:59:59.000Z

55

PHYSICAL REVIEW A 88, 043428 (2013) Transient absorption spectra of the laser-dressed hydrogen atom  

E-Print Network [OSTI]

PHYSICAL REVIEW A 88, 043428 (2013) Transient absorption spectra of the laser-dressed hydrogen atom.043428 PACS number(s): 32.80.Rm, 42.65.Ky I. INTRODUCTION Transient absorption spectra of laser-dressed atoms absorption spectra of hydrogen atoms based on numerical solutions of the time-dependent Schr¨odinger equation

Chu, Shih-I

56

Direct atomic flux measurement of electron-beam evaporated yttrium with a diode-laser-based atomic absorption monitor at 668 nm  

E-Print Network [OSTI]

with a diode-laser-based atomic absorption AA monitor at 668 nm. Atomic number density and velocity were measured through absorption and Doppler shift measurements to provide the atomic flux. The AA previously developed diode-laser-based atomic absorption AA monitors for atomic density measurements

Fejer, Martin M.

57

Delta-doping of boron atoms by photoexcited chemical vapor deposition  

SciTech Connect (OSTI)

Boron delta-doped structures in Si crystals were fabricated by means of photoexcited chemical vapor deposition (CVD). Core electronic excitation with high-energy photons ranging from vacuum ultraviolet to soft x rays decomposes B{sub 2}H{sub 6} molecules into fragments. Combined with in situ monitoring by spectroscopic ellipsometry, limited number of boron hydrides can be delivered onto a Si(100) surface by using the incubation period before the formation of a solid boron film. The boron-covered surface is subsequently embedded in a Si cap layer by Si{sub 2}H{sub 6} photo-excited CVD. The crystallinity of the Si cap layer depended on its thickness and the substrate temperature. The evaluation of the boron depth profile by secondary ion mass spectroscopy revealed that boron atoms were confined within the delta-doped layer at a concentration of 2.5 x 10{sup 20} cm{sup -3} with a full width at half maximum of less than 9 nm, while the epitaxial growth of a 130-nm-thick Si cap layer was sustained at 420 deg. C.

Akazawa, Housei [NTT Microsystem Integration Laboratories, 3-1 Morinosato Wakamiya, Atsugi, Kanagawa 243-0198 (Japan)

2012-03-15T23:59:59.000Z

58

E-Print Network 3.0 - atomic recoil laser Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

laser Search Powered by Explorit Topic List Advanced Search Sample search results for: atomic recoil laser Page: << < 1 2 3 4 5 > >> 1 Contrast Interferometry using Bose-Einstein...

59

E-Print Network 3.0 - atomic iodine laser Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

iodine laser Search Powered by Explorit Topic List Advanced Search Sample search results for: atomic iodine laser Page: << < 1 2 3 4 5 > >> 1 JOURNALDE PHYSIQUEIV ColloqueC7,...

60

E-Print Network 3.0 - atom laser driven Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

laser driven Search Powered by Explorit Topic List Advanced Search Sample search results for: atom laser driven Page: << < 1 2 3 4 5 > >> 1 (For McGraw-Hill 1999 Yearbook of...

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

E-Print Network 3.0 - atom-photon pair laser Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

photon pair laser Search Powered by Explorit Topic List Advanced Search Sample search results for: atom-photon pair laser Page: << < 1 2 3 4 5 > >> 1 Observation of Entanglement of...

62

A three-beam water vapor sensor system for combustion diagnostics using a 1390 nm tunable diode laser  

SciTech Connect (OSTI)

H{sub 2}O(v) is an important species in combustion and hypersonic flow measurements because it is a primary combustion product. Measurements of water vapor can be used to determine performance parameters, such as extent and efficiency of combustion in propulsion and aerodynamics facilities. Water vapor concentration measurement in these high-temperature hypervelocity combustion conditions requires very high sensitivity and fast time response. A three-beam diode laser H{sub 2}O(v) measurement system for nonintrusive combustion diagnostics has been developed at NASA Langley Research Center and successfully tested and installed at GASL NASA HYPULSE facility for routine operation. The system was built using both direct laser absorption spectroscopy and frequency modulation laser spectroscopy. The output beam from a distributed feedback (DFB) InGaAsP diode laser (emitting around 1.39 {micro}m) is split into three equal-powered equal-distanced parallel beams with separation of 9 mm. With three beams, the authors are able to obtain water vapor number densities at three locations. Frequency modulation spectroscopy technique is used to achieve high detection sensitivity. The diode laser is modulated at radio frequency (RF), while the wavelength of the diode laser is tuned to scan over a strong water vapor absorption line. The detected RF signal is then demodulated at the fundamental frequency of the modulation (one-F demodulation). A working model and a computer software code have been developed for data process and data analysis. Water vapor number density measurements are achieved with consideration of temperature dependence. Experimental results and data analysis will be presented.

Wang, L.G. [Coll. of William and Mary, Williamsburg, VA (United States). Dept. of Physics; Vay, S. [National Aeronautics and Space Administration, Hampton, VA (United States). Langley Research Center

1995-12-31T23:59:59.000Z

63

E-Print Network 3.0 - atomic vapour laser Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Vogl and Martin Weitz Summary: to forego the initial heating required for vapour- ising the rubidium atoms. The laser cooling method could... - ditional energy that...

64

Atomic absorption monitor for deposition process control of aluminum at 394 nm using frequency-doubled diode laser  

E-Print Network [OSTI]

Atomic absorption monitor for deposition process control of aluminum at 394 nm using frequency November 1995 A monitor for Al vapor density based on atomic absorption AA using a frequency of atomic absorption AA as a monitor for thickness and composition control in physical vapor deposi- tion

Fejer, Martin M.

65

E-Print Network 3.0 - alkali atom vapor Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

a vapor cell magneto-optical trap. 1999 American... to the vacuum pumps or due to adsorption of the ... Source: Jin, Deborah - JILA, University of Colorado at Boulder...

66

Low-Cost, Modular Electrothermal Vaporization System for Inductively Coupled Plasma Atomic Emission Spectrometry  

Science Journals Connector (OSTI)

In this investigation, commercially available tungsten filaments were employed to electrothermally vaporize liquid samples prior to their introduction into an inductively coupled...

Levine, Keith; Wagner, Karl A; Jones, Bradley T

1998-01-01T23:59:59.000Z

67

E-Print Network 3.0 - atomic vapor deposited Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Articles Surfactant-Catalyzed Chemical Vapor Deposition of Copper Thin Films Eui Seong Hwang... and demonstrated for deposition of copper thin films from ... Source:...

68

Growth of vertical-cavity surface emitting lasers by metalorganic vapor phase epitaxy  

SciTech Connect (OSTI)

We present growth and characterization of visible and near-infrared vertical-cavity surface emitting lasers (VCSELs) grown by metalorganic vapor phase epitaxy. Discussions on the growth issue of VCSEL materials include growth rate and composition control using an {ital in}{ital situ} normal-incidence reflectometer, comprehensive p- and n-type doping study in AlGaAs by CCl{sub 4} and Si{sub 2}H{sub 6} over the entire composition range, and optimization of ultra-high material uniformity. We also demonstrate our recent achievements of all-AlGaAs VCSELs which include the first room-temperature continuous- wave demonstration of 700-nm red VCSELs and high-efficiency and low- threshold voltage 850-nm VCSELs.

Hou, H.Q.; Hammons, B.E.; Crawford, M.H.; Lear, K.L.; Choquette, K.D.

1996-10-01T23:59:59.000Z

69

Laser resonance heating of atoms in a capillary. Measuring the accommodation coefficient of the kinetic energy of the atoms  

Science Journals Connector (OSTI)

It has been experimentally detected that the laser irradiation of a rarefied flux of atoms in a capillary causes a reduction of their concentration at the output. It is established...

Bonch-Bruevich, A M; Vartanyan, T A; Przhibel'skii, S G; Smirnov, V N; Khromov, V V

2004-01-01T23:59:59.000Z

70

Dipole and quadrupole forces exerted on atoms in laser fields: The nonperturbative approach  

SciTech Connect (OSTI)

Manipulation of cold atoms by lasers has so far been studied solely within the framework of the conventional dipole approximation, and the atom-light interaction has been treated using low order perturbation theory. Laser control of atomic motions has been ascribed exclusively to the corresponding light-induced dipole forces. In this work, we present a general theory to derive the potential experienced by an atom in a monochromatic laser field in a context analogous to the Born-Oppenheimer approximation for molecules in the field-free case. The formulation goes beyond the dipole approximation and gives rise to the field-atom coupling potential terms which so far have not been taken into consideration in theoretical or experimental studies. Contrary to conventional approaches, our method is based upon the many electron Floquet theory and remains valid also for high intensity laser fields (i.e., for a strongly nonperturbative atom-light interaction). As an illustration of the developed theory, we investigate the trapping of cold atoms in optical lattices. We find that for some atoms for specific laser parameters, despite the absence of the dipole force, the laser trapping is still possible due to the electric quadrupole forces. Namely, we show that by using realistic laser parameters one can form a quadrupole optical lattice which is sufficiently strong to trap Ca and Na atoms.

Sindelka, Milan; Moiseyev, Nimrod [Department of Chemistry and Minerva Center of Nonlinear Physics in Complex Systems, Technion, Israel Institute of Technology, Haifa 32000 (Israel); Cederbaum, Lorenz S. [Theoretische Chemie, Physikalisch-Chemisches Institut, Universitaet Heidelberg, D-69120 Heidelberg (Germany)

2006-11-15T23:59:59.000Z

71

Laser-excited atomic fluorescence spectrometry in a graphite furnace with an  

E-Print Network [OSTI]

Laser-excited atomic fluorescence spectrometry in a graphite furnace with an optical parametric oscillator laser for sequential multi-element determination of cadmium, cobalt, lead, manganese and thallium, for the ® rst time, that solid-state lasers required for analysis (ml or mg) and the technique has direct based

Michel, Robert G.

72

E-Print Network 3.0 - atomic vapor density Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

T is temperature, Qris... F, is magnetic force, J is vapor plasma current density, c is speed of light, and B is magnetic flux... density. The induced magnetic force will act as...

73

Optical coatings of variable refractive index and high laser-resistance from physical-vapor-deposited perfluorinated amorphous polymer  

DOE Patents [OSTI]

Variable index optical single-layers, optical multilayer, and laser-resistant coatings were made from a perfluorinated amorphous polymer material by physical vapor deposition. This was accomplished by physically vapor depositing a polymer material, such as bulk Teflon AF2400, for example, to form thin layers that have a very low refractive index (.about.1.10-1.31) and are highly transparent from the ultra-violet through the near infrared regime, and maintain the low refractive index of the bulk material. The refractive index can be varied by simply varying one process parameter, either the deposition rate or the substrate temperature. The thus forming coatings may be utilized in anti-reflectors and graded anti-reflection coatings, as well as in optical layers for laser-resistant coatings at optical wavelengths of less than about 2000 nm.

Chow, Robert (Livermore, CA); Loomis, Gary E. (Livermore, CA); Thomas, Ian M. (Livermore, CA)

1999-01-01T23:59:59.000Z

74

Optical coatings of variable refractive index and high laser-resistance from physical-vapor-deposited perfluorinated amorphous polymer  

DOE Patents [OSTI]

Variable index optical single-layers, optical multilayer, and laser-resistant coatings were made from a perfluorinated amorphous polymer material by physical vapor deposition. This was accomplished by physically vapor depositing a polymer material, such as bulk Teflon AF2400, for example, to form thin layers that have a very low refractive index (ca. 1.10--1.31) and are highly transparent from the ultra-violet through the near infrared regime, and maintain the low refractive index of the bulk material. The refractive index can be varied by simply varying one process parameter, either the deposition rate or the substrate temperature. The thus forming coatings may be utilized in anti-reflectors and graded anti-reflection coatings, as well as in optical layers for laser-resistant coatings at optical wavelengths of less than about 2000 nm. 2 figs.

Chow, R.; Loomis, G.E.; Thomas, I.M.

1999-03-16T23:59:59.000Z

75

Atomic-level investigation of the growth of Si/Ge by ultrahigh vacuum chemical vapor deposition  

SciTech Connect (OSTI)

Si and Ge films can be prepared under ultrahigh vacuum conditions by chemical vapor deposition using disilane and digermane as source gases. These gases offer a high sticking probability, and are suitable for atomic layer epitaxy. Using synchrotron radiation photoemission spectroscopy and scanning tunneling microscopy, we have examined the surface processes associated with the heteroepitaxial growth of Ge/Si. The measured surface-induced shifts and chemical shifts of the Si 2p and Ge 3d core levels allow us to identify the surface species and to determine the surface chemical composition, and this information is correlated with the atomic features observed by scanning tunneling microscopy. Issues related to precursor dissociation, attachment to dangling bonds, diffusion, surface segregation, growth morphology, and pyrolytic reaction pathways will be discussed. {copyright} {ital 1997 American Vacuum Society.}

Lin, D. [Institute of Physics, National Chiao-Tung University, Hsinchu, Taiwan, Republic of (China)] [Institute of Physics, National Chiao-Tung University, Hsinchu, Taiwan, Republic of (China); Miller, T.; Chiang, T. [Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States)] [Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801 (United States)

1997-05-01T23:59:59.000Z

76

Determination of the concentrations of magnesium and aluminum in alloys by laser produced atomic emission spectroscopy  

E-Print Network [OSTI]

DETERMINATION OF THE CONCENTRATIONS OF MAGNESIUM AND ALUiiINUM IN ALLOYS BY LASER PRODUCED ATOMIC EMISSION SPECTROSCOPY A Thesis by WILLIAM MONROE ASHE Submitted to the Office of Graduate Studies of Texas A&M University in partial... fulfillment of the reqmrements for the degree of MASTER OF SCIENCE December 1997 Major Subject: Physics DETERMINATION OF THE CONCENTRATIONS OF MAGNESIUM AND ALUMINUM ALLOYS BY LASER PRODUCED ATOMIC EMISSION SPECTROSCOPY A Thesis by WILLIAM MONROE ASHE...

Ashe, William Monroe

2012-06-07T23:59:59.000Z

77

Lab Breakthrough: X-ray Laser Captures Atoms and Molecules in Action |  

Broader source: Energy.gov (indexed) [DOE]

X-ray Laser Captures Atoms and Molecules in X-ray Laser Captures Atoms and Molecules in Action Lab Breakthrough: X-ray Laser Captures Atoms and Molecules in Action July 18, 2012 - 12:51pm Addthis The Linac Coherent Light Source at SLAC is the world's most powerful X-ray laser, which helps researchers understand the extreme conditions found in the hearts of stars and giant planets guiding research into nuclear fusion, the mechanism that powers the sun. View the entire Lab Breakthrough playlist. Michael Hess Michael Hess Former Digital Communications Specialist, Office of Public Affairs How is the LCLS different? Rather than accelerate particles to collide them, it accelerates particles in a special way to create extremely bright bunches of photons. These pulses are about 10 billion times brighter and one thousand

78

Identification of vapor-phase chemical warfare agent simulants and rocket fuels using laser-induced breakdown spectroscopy  

SciTech Connect (OSTI)

Application of laser-induced breakdown spectroscopy (LIBS) to the identification of security threats is a growing area of research. This work presents LIBS spectra of vapor-phase chemical warfare agent simulants and typical rocket fuels. A large dataset of spectra was acquired using a variety of gas mixtures and background pressures and processed using partial least squares analysis. The five compounds studied were identified with a 99% success rate by the best method. The temporal behavior of the emission lines as a function of chamber pressure and gas mixture was also investigated, revealing some interesting trends that merit further study.

Stearns, Jaime A.; McElman, Sarah E.; Dodd, James A.

2010-05-01T23:59:59.000Z

79

Atomic/Molecular-Level Simulations of LaserMaterials Interactions  

E-Print Network [OSTI]

- acter of the cascade of interrelated processes triggered by the laser excitation. These processes an increasingly important role in the investigation of complex and highly nonequilibrium processes involved in short-pulse laser processing and surface modification. This chapter provides an overview of recent

Zhigilei, Leonid V.

80

Periodic index separate confinement heterostructure multiple quantum well laser' n by organometailic vapor  

E-Print Network [OSTI]

similar conditions. The PINSCH laser uses cladding layers comprised of periodic semiconductor multilayers applied to 980 nm InGaAs/AlGaAs quantum well lasers.6 The cladding layers consist of alternating layersPeriodic index separate confinement heterostructure multiple quantum well laser' n

Florida, University of

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Design and Fabrication of a Chip-based Continuous-wave Atom Laser  

E-Print Network [OSTI]

We present a design for a continuous-wave (CW) atom laser on a chip and describe the process used to fabricate the device. Our design aims to integrate quadrupole magnetic guiding of ground state Rb atoms with continuous surface adsorption evaporative cooling to create a continuous Bose-Einstein condensate; out-coupled atoms from the condensate should realize a CW atom laser. We choose a geometry with three wires embedded in a spiral pattern in a silicon subtrate. The guide features an integrated solenoid to mitigate spin-flip losses and provide a tailored longitudinal magnetic field. Our design also includes multiple options for atom interferometry: accomodations are in place for laser-generated atom Fabry-Perot and Mach-Zehnder interferometers, and a pair of atomic beam X-splitters is incorporated for an all-magnetic atom Mach-Zehnder setup. We demonstrate the techniques necessary to fabricate our device using existing micro- and nano-scale fabrication equipment, and discuss future options for modified desi...

Power, E P; Vanderelzen, B; Herrera-Fierro, P; Murphy, R; Yalisove, S M; Raithel, G

2012-01-01T23:59:59.000Z

82

THz Quantum Cascade Lasers Grown by Low-Pressure Metalorganic Vapor Phase Epitaxy  

Science Journals Connector (OSTI)

A terahertz quantum cascade laser (QCL) has been successfully grown by low-pressure MOVPE. Very high quality semiconductor interfaces are demonstrated as well as very promising lasing...

Sirigu, Lorenzo; Rudra, Alok; Amanti, Maria I; Scalari, Giacomo; Fischer, Milan; Giovannini, Marcella; Faist, Jerome; Kapon, Eli

83

Shaping coherent excitation of atoms and molecules by a train of ultrashort laser pulses  

E-Print Network [OSTI]

We propose a mechanism to produce a superposition of atomic and molecular states by a train of ultrashort laser pulses combined with weak control fields. By adjusting the repetition rate of the pump pulses and the intensity of the coupling laser, one can suppress a transition while simultaneously enhancing the desired transitions. As an example, various superpositions of vibrational states of the $K_2$ molecule are shown.

Anahit Gogyan; Stephane Guerin; Yuri Malakyan

2014-11-17T23:59:59.000Z

84

Nonlinear dynamics of ionization stabilization of atoms in intense laser fields  

E-Print Network [OSTI]

We revisit the stabilization of ionization of atoms subjected to a superintense laser pulse using nonlinear dynamics. We provide an explanation for the lack of complete ionization at high intensity and for the decrease of the ionization probability as intensity is increased. We investigate the role of each part of the laser pulse (ramp-up, plateau, ramp-down) in this process. We emphasize the role of the choice for the ionization criterion, energy versus distance criterion.

Michael Norman; C. Chandre; T. Uzer; Peijie Wang

2014-12-06T23:59:59.000Z

85

Laser safety information for the Atomic, Molecular and Optical (AMO) Physics Labs at Lehigh University modified from the laser safety program developed by the office of Environmental  

E-Print Network [OSTI]

1 Laser safety information for the Atomic, Molecular and Optical (AMO) Physics Labs at Lehigh University modified from the laser safety program developed by the office of Environmental Health and Safety using the following reference materials: I. American National Standards for Safe Use of Lasers - ANSI Z

Huennekens, John

86

Bose–Einstein condensation transition studies for atoms confined in Laguerre–Gaussian laser modes  

Science Journals Connector (OSTI)

Multiply-connected traps for cold, neutral atoms fix vortex cores of quantum gases. Laguerre–Gaussian laser modes are ideal for such traps due to their phase stability. We report theoretical calculations of the Bose–Einstein condensation transition properties and thermal characteristics of neutral atoms trapped in multiply connected geometries formed by Laguerre–Gaussian (LGpl) beams. Specifically, we consider atoms confined to the anti-node of a LG01 laser mode detuned to the red of an atomic resonance frequency, and those confined in the node of a blue-detuned LG11 beam. We compare the results of using the full potential to those approximating the potential minimum with a simple harmonic oscillator potential. We find that deviations between calculations of the full potential and the simple harmonic oscillator can be up to 3%–8% for trap parameters consistent with typical experiments.

T.G. Akin; Sharon Kennedy; Ben Dribus; Jeremy L. Marzuola; Lise Johnson; Jason Alexander; E.R.I. Abraham

2012-01-01T23:59:59.000Z

87

Analysis of Na and Ba in an atomic fluorescence method with excitation by a pulsed dye laser with lamp pumping  

SciTech Connect (OSTI)

Among the laser methods used in atomic spectroscopy, atomic fluorescence resonance spectroscopy together with an atomic ionization technique make it possible to work with individual atoms. This paper reports on the determination of Na and Ba in aqueous solutions of their salts with atomic fluorescence analysis performed wih a dye laser and lamp pumping, the pulse of generation having a length of 1-2 usec. The detection limit of elements in atomic fluorescence analysis performed wih dye lasers with lamp pumping can be reduced by increasing the spectral density of the laser radiation through narrowing the line of generation, by employing other dyes to excite lines of greater intensity, by improving the recording system of the fluorescence spectra, and by improving the atomization of the samples to be analyzed.

Kukvshim, V.G.

1986-04-01T23:59:59.000Z

88

Entropy Driven Atomic Motion in Laser-Excited Bismuth  

SciTech Connect (OSTI)

We introduce a thermodynamical model based on the two-temperature approach in order to fully understand the dynamics of the coherent A{sub 1g} phonon in laser-excited bismuth. Using this model, we simulate the time evolution of (111) Bragg peak intensities measured by Fritz et al.[Science 315, 633 (2007)] in femtosecond x-ray diffraction experiments performed on a bismuth film for different laser fluences. The agreement between theoretical and experimental results is striking not only because we use fluences very close to the experimental ones but also because most of the model parameters are obtained from ab initio calculations performed for different electron temperatures.

Giret, Y.; Gelle, A.; Arnaud, B. [Institut de Physique de Rennes (IPR), UMR UR1-CNRS 6251, Campus de Beaulieu-Bat 11 A, 35042 Rennes Cedex, France, EU (France)

2011-04-15T23:59:59.000Z

89

Synchronization of internal and external degrees of freedom of atoms in a standing laser wave  

E-Print Network [OSTI]

We consider dissipative dynamics of atoms in a strong standing laser wave and find a nonlinear dynamical effect of synchronization between center-of-mass motion and internal Rabi oscillations. The synchronization manifests itself in the phase space as limit cycles which may have different periods and riddled basins of attraction. The effect can be detected in the fluorescence spectra of atoms as equidistant sideband frequencies with the space between adjacent peaks to be inversely proportional to the value of the period of the respective limit cycle. With increasing the intensity of the laser field, we observe numerically cascades of bifurcations that eventually end up in settling a strange chaotic attractor. A broadband noise is shown to destroy a fine structure of the bifurcation scenario, but prominent features of period-1 and period-3 limit cycles survive under a weak noise. The character of the atomic motion is analyzed with the help of the friction force whose zeroes are attractor or repellor points in the velocity space. We find ranges of the laser parameters where the atomic motion resembles a random but deterministic walking of atoms erratically jumping between different wells of the optical potential. Such a random walking is shown to be fractal in the sense that the measured characteristic of the motion, time of exit of atoms from a given space of the standing wave, is a complicated function that has a self-similar structure with singularities on a Cantor set of values of one of the control parameters.

V. Yu. Argonov; S. V. Prants

2004-09-17T23:59:59.000Z

90

Mass Spectroscopy and Reaction Studies of Laser-Vaporized Clusters from Metal-Doped Carbon Materials  

E-Print Network [OSTI]

C50 + LaC60 + (40) 30 40 50 60 70 Number of Carbon Atoms Intensity(arb.units) (a) Positive La Number of Carbon Atoms Intensity(arbitrary) C43 ­ C44 ­ Mass (amu) LaC32 ­ (a) (b) Fig. 2 Even distribution. 440 460 480 500 36 38 40 42 Number of Carbon Atoms Intensity(arbitrary) (a) as injected (b

Maruyama, Shigeo

91

High–intensity lasers: interactions with atoms, molecules and clusters  

Science Journals Connector (OSTI)

...tra from around 2500-atom xenon clusters irradiated by 2 1016...charge states up to 12+ in xenon and 8+ in krypton at an intensity...process converts the coherent oscillation energy of the electron cloud...result of a resonantly driven oscillation of the entire cluster elec...

1998-01-01T23:59:59.000Z

92

Atomistic modeling of femtosecond laser-induced melting and atomic mixing in Au film Cu substrate system  

E-Print Network [OSTI]

, including laser surface alloying, cladding, annealing, and hardening, e.g. [1­6]. The improvement of surfaceAtomistic modeling of femtosecond laser-induced melting and atomic mixing in Au film ­ Cu substrate modification by laser irradiation is in the core of many modern processing and fabrication techniques

Zhigilei, Leonid V.

93

Analysis of atomic and ion debris features of laser-produced Sn and Li plasmas  

E-Print Network [OSTI]

Analysis of atomic and ion debris features of laser-produced Sn and Li plasmas R. W. Coons,a S. S. Harilal, D. Campos, and A. Hassanein School of Nuclear Engineering and Center for Materials Under Extreme provide a CE nearly twice that of Li. However, the kinetic energies of Sn ions are considerably higher

Harilal, S. S.

94

Steady-state quantum statistics of a non-Markovian atom laser. II  

Science Journals Connector (OSTI)

We present a steady-state analysis of a quantum-mechanical model of an atom laser. A single-mode atomic trap coupled to a continuum of external modes is driven by a saturable pumping mechanism. In the dilute flux regime, where atom-atom interactions are negligible in the output, we find an analytic form for the linewidth and frequency shift of the laser. This result does not make the Born-Markov approximation, but is based on the far less restrictive “self-consistent Markov approximation.” The more exact treatment has a different effective damping rate and occupation of the lasing mode, as well as a shifted frequency and linewidth of the output. We examine gravitational damping numerically, finding linewidths and frequency shifts for a range of pumping rates. We treat mean-field damping analytically, finding a memory function for the Thomas-Fermi regime. The occupation and linewidth are found to have a nonlinear scaling behavior which has implications for the stability of atom lasers.

A. S. Bradley; J. J. Hope; M. J. Collett

2003-12-22T23:59:59.000Z

95

Application of atomic vapor laser isotope separation to the enrichment of mercury  

SciTech Connect (OSTI)

Workers at GTE/Sylvania have shown that the efficiency of fluorescent lighting may be markedly improved using mercury that has been enriched in the /sup 196/Hg isotope. A 5% improvement in the efficiency of fluorescent lighting in the United States could provide a savings of $450 million dollars in the corresponding reduction of electrical power consumption. We discuss the results of recent work done at our laboratory to develop a process for enriching mercury. The discussion centers around the results of spectroscopic measurements of excited-state lifetimes, photoionization cross sections, and isotope shifts.

Crane, J.; Erbert, G.; Paisner, J.; Chen, H.; Chiba, Z.; Beeler, R.; Combs, R.; Mostek, S.

1986-09-01T23:59:59.000Z

96

Laser vaporization clusters from metal loaded graphite used for SWNT generation  

E-Print Network [OSTI]

, these metal-carbon clusters were proved to be very reactive. 40 60 80 100 Number of Carbon Atoms Intensity of Carbon Atoms Intensity(arbitrary) (a) Positive (b) Negative Fig2. Enlargement of C70 to C73 C74 C76 C72, The Univ. of Tokyo In order to study the generation mechanism of SWNTs, we have studied metal-carbon binary

Maruyama, Shigeo

97

Laser photochemical growth of amorphous silicon at low temperatures and comparison with thermal chemical vapor deposition  

SciTech Connect (OSTI)

Pulsed ArF (193 nm) excimer laser radiation has been used to dissociate disilane (Si/sub 2/H/sub 6/, resulting in photochemically controlled deposition of amorphous Si thin films. A high stability HeNe (6328 A) laser was used for precise in situ monitoring of film deposition rates, under varying deposition conditions. A helium window purge nearly eliminated Si film deposition on the chamber windows. With the excimer laser beam parallel to the substrate, deposition of amorphous Si can be controlled entirely by the photon fluence (negligible background thermal growth) at temperatures from room temperature up to /approximately/400/degree/C. Reasonable photolytic deposition rate (>1 A/sec) are combined with 'digital' control of film thickness (/approx gt/0.02 A/laser pulse). Activation energies of 1.50 (+-0.1) eV and 0.09 (+-0.02) eV were found for pyrolytic and photolytic deposition, respectively. 15 refs., 3 figs.

Eres, D.; Lowndes, D.H.; Geohegan, D.B.; Mashburn, D.N.

1987-01-01T23:59:59.000Z

98

Wavelength-modulation laser hygrometer for ultrasensitive detection of water vapor in  

E-Print Network [OSTI]

- bines wavelength-modulation absorption spectros- copy WMS 12­16 that uses near-infrared InGaAsP diode is measured by use of a near-infrared diode laser and wavelength-modulation absorption spectroscopy. Humidity in the spectral regions of strongest water absorption. Sensitive single-mode cavity ring-down techniques based

99

Laser Irradiated Enhancement of the Atomic Electron Capture Rate in search of New Physics  

E-Print Network [OSTI]

Electron capture processes are important in the search for new physics. In this context, a high capture rate is desired. We investigate the possibility of enhancing the electron capture rate by irradiating laser beam to ''atom''. The possibility of such enhancement can be understood as a consequence of an enhancement of the electron wave function at the origin, $\\Psi (0)$, through an increased effective mass of the electron. We find that an order of magnitude enhancement can be realized by using a laser with intensity on the order of $10^{10}$ W/mm$^2$ and a photon energy on the order of $10^{-3}$ eV.

Takaaki Nomura; Joe Sato; Takashi Shimomura

2007-06-16T23:59:59.000Z

100

Toward atomic resolution diffractive imaging of isolated molecules with x-ray free-electron lasers  

E-Print Network [OSTI]

We give a detailed account of the theoretical analysis and the experimental results of an x-ray-diffraction experiment on quantum-state selected and strongly laser-aligned gas-phase ensembles of the prototypical large asymmetric rotor molecule 2,5-diiodobenzonitrile, performed at the Linac Coherent Light Source [Phys. Rev. Lett. 112, 083002 (2014)]. This experiment is the first step toward coherent diffractive imaging of structures and structural dynamics of isolated molecules at atomic resolution, i. e., picometers and femtoseconds, using x-ray free-electron lasers.

Stern, Stephan; Filsinger, Frank; Rouzée, Arnaud; Rudenko, Artem; Johnsson, Per; Martin, Andrew V; Barty, Anton; Bostedt, Christoph; Bozek, John D; Coffee, Ryan N; Epp, Sascha; Erk, Benjamin; Foucar, Lutz; Hartmann, Robert; Kimmel, Nils; Kühnel, Kai-Uwe; Maurer, Jochen; Messerschmidt, Marc; Rudek, Benedikt; Starodub, Dmitri G; Thøgersen, Jan; Weidenspointner, Georg; White, Thomas A; Stapelfeldt, Henrik; Rolles, Daniel; Chapman, Henry N; Küpper, Jochen

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
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101

Laser-Cooled Lithium Atoms: A New Source for Focused Ion Beams  

E-Print Network [OSTI]

Laser-Cooled Lithium Atoms: A New Source for Focused Ion Beams P R O J E C T L E A D E R : Jabez Mc) to provide ions for a focused ion beam (FIB) capable of non-destructive imaging. K E Y A C C O M P L I S H M mounted on a commercial focused ion beam system, creating the world's first lithium ion microscope

102

Impact of electron collision mixing on the delay times of an electron beam excited atomic xenon laser  

SciTech Connect (OSTI)

The atomic xenon (5d {r arrow} 6p) infrared laser has been experimentally and theoretically investigated using a short pulse (30 ns) high power (1-10 MW/cm{sup 3}) coaxial electron beam excitation source. In most cases, laser oscillation is not observed during the e-beam current pulse. Laser pulses of 100's of ns duration are subsequently obtained, however, with oscillation beginning 60-800 ns after the current pulse terminates. Results from a computer model for the xenon laser reproduce the experimental values, and show that oscillation begins when the fractional electron density decays below a critical value of {approx} 0.2-0.8 {times} 10{sup 6}. These results lend credance to the proposal that electron collision mixing of the laser levels limits the maximum value of specific power deposition which may be used to efficiently excite the atomic xenon laser on a quasi-CW basis.

Peters, P.J. (Dept. of Applied Physics, Univ. of Twente, 7500 AE Enshede (NL)); Lan, Y.F. (Inst. of Electronics, Beijing (CN)); Ohwa, M. (Dept. of Electrical Engineering, Keio Univ., Yokahama (JP)); Kushner, M.J. (Dept. of Electrical and Computer Engineering, Univ. of Illinois, Urbana, IL (US))

1990-11-01T23:59:59.000Z

103

Forced convection and transport effects during hyperbaric laser chemical vapor deposition  

SciTech Connect (OSTI)

This work explores mass transport processes during HP-LCYD, including the transverse forced-flow of precursor gases through a nozzle to enhance fiber growth rates. The use of laser trapping and suspension of nano-scale particles in the precursor flow is also described, providing insights into the nature of the gas flow, including jetting from the fiber tip and thermodiffusion processes near the reaction zone. The effects of differing molecular-weight buffer gases is also explored in conjunction with the Soret effect, and it is found that nucleation at the deposit surface (and homogeneous nucleation in the gas phase) can be enhanced/ retarded, depending on the buffer gas molecular weight. To demonstrate that extensive microstructures can be grown simultaneously, three-dimensional fiber arrays are also grown in-parallel using diffractive optics--without delatory effects from neighboring reaction sites.

Maxwell, James L [Los Alamos National Laboratory; Chavez, Craig A [Los Alamos National Laboratory; Espinoza, Miguel [Los Alamos National Laboratory; Black, Marcie [Los Alamos National Laboratory; Maskaly, Karlene [Los Alamos National Laboratory; Boman, Mats [UPPSALA UNIV

2009-01-01T23:59:59.000Z

104

Time-resolved diffraction profiles and atomic dynamics in short-pulse laser-induced structural transformations: Molecular dynamics study  

E-Print Network [OSTI]

Time-resolved diffraction profiles and atomic dynamics in short-pulse laser-induced structural dynamics simulations of a 20 nm Au film irradiated with 200 fs laser pulses of different intensity in time-resolved x-ray and electron diffraction experiments. Three processes are found to be responsible

Zhigilei, Leonid V.

105

Application of two-photon laser-induced fluorescence for visualization of water vapor in combustion environments  

Science Journals Connector (OSTI)

Investigations concerning the potential for the visualization of water vapor in combustion processes have been made. The water molecules were excited through a two-photon excitation...

Neij, Hans; Aldén, Marcus

1994-01-01T23:59:59.000Z

106

Using Lasers and X-rays to Reveal the Motion of Atoms and Electrons  

ScienceCinema (OSTI)

July 7, 2009 Berkeley Lab summer lecture: The ultrafast motion of atoms and electrons lies at the heart of chemical reactions, advanced materials with exotic properties, and biological processes such as the first event in vision. Bob Schoenlein, Deputy Director for Science at the Advanced Light Source, will discuss how such processes are revealed by using laser pulses spanning a millionth of a billionth of a second, and how a new generation of light sources will bring the penetrating power of x-rays to the world of ultrafast science

Bob Schoenlein

2010-01-08T23:59:59.000Z

107

Laser sampling system for an inductively-coupled atomic emission spectrometer. Final report  

SciTech Connect (OSTI)

A laser sampling system was attached to a Perkin Elmer Optima 3000 inductively-coupled plasma, atomic emission spectrometer that was already installed and operating in the Chemistry and Geochemistry Department at the Colorado School of Mines. The use of the spectrometer has been highly successful. Graduate students and faculty from at least four different departments across the CSM campus have used the instrument. The final report to NSF is appended to this final report. Appendices are included which summarize several projects utilizing this instrument: acquisition of an inductively-coupled plasma atomic emission spectrometer for the geochemistry program; hydrogen damage susceptibility assessment for high strength steel weldments through advanced hydrogen content analysis, 1996 and 1997 annual reports; and methods for determination of hydrogen distribution in high strength steel welds.

NONE

1998-02-15T23:59:59.000Z

108

Innovative lasers for uranium isotope separation. [Progress report  

SciTech Connect (OSTI)

Copper vapor lasers have important applications to uranium atomic vapor laser isotope separation (AVLIS). The authors have spent the first two years of their project investigating two innovative methods of exciting/pumping copper vapor lasers which have the potential to improve the efficiency and scaling of large laser systems used in uranium isotope separation. Experimental research has focused on the laser discharge kinetics of (1) microwave, and (2) electron beam excitation/pumping of large-volume copper vapor lasers. During the first year, the experiments have been designed and constructed and initial data has been taken. During the second year these experiments have been diagnosed. Highlights of some of the second year results as well as plans for the future include the following: Microwave resonant cavity produced copper vapor plasmas at 2.45 GHz, have been investigated. A CW (0--500 W) signal heats and vaporizes the copper chloride to provide the atomic copper vapor. A pulsed (5 kW, 0.5--5kHz) signal is added to the incoming CW signal via a hybrid mixer to excite the copper states to the laser levels. An enhancement of the visible radiation has been observed during the pulsed pardon of the signal. Electrical probe measurements have been implemented on the system to verify the results of the electromagnetic model formulated last year. Laser gain measurements have been initiated with the use of a commercial copper vapor laser. Measurements of the spatial profile of the emission are also currently being made. The authors plan to increase the amount of pulsed microwave power to the system by implementing a high power magnetron. A laser cavity will be designed and added to this system.

Brake, M.L.; Gilgenbach, R.M.

1991-06-01T23:59:59.000Z

109

Proposed method for laser spectroscopy of pionic helium atoms to determine the charged-pion mass  

E-Print Network [OSTI]

Metastable pionic helium ($\\pi{\\rm He}^+$) is a three-body atom composed of a helium nucleus, an electron occupying the $1s$ ground state, and a negatively charged pion $\\pi^-$ in a Rydberg state with principal- and orbital angular momentum quantum numbers of $n\\sim \\ell+1\\sim 16$. We calculate the spin-independent energies of the $\\pi{\\rm ^3He}^+$ and $\\pi{\\rm ^4He}^+$ isotopes in the region $n=15$--19. These include relativistic and quantum electrodynamics corrections of orders $R_{\\infty}\\alpha^2$ and $R_{\\infty}\\alpha^3$ in atomic units, where $R_{\\infty}$ and $\\alpha$ denote the Rydberg and fine structure constants. The fine-structure splitting due to the coupling between the electron spin and the orbital angular momentum of the $\\pi^-$, and the radiative and Auger decay rates of the states are also calculated. Some states $(n,\\ell)=(16,15)$ and $(17,16)$ retain nanosecond-scale lifetimes against $\\pi^-$ absorption into the helium nucleus. We propose to use laser pulses to induce $\\pi^-$ transitions from these metastable states, to states with large ($\\sim 10^{11}$ s$^{-1}$) Auger rates. The $\\pi{\\rm He}^{2+}$ ion that remains after Auger emission of the $1s$ electron undergoes Stark mixing with the $s$, $p$, and $d$ states during collisions with the helium atoms in the experimental target. This leads to immediate nuclear absorption of the $\\pi^-$. The resonance condition between the laser beam and the atom is thus revealed as a sharp spike in the rates of neutrons, protons, deuterons, and tritons that emerge....(continued)

Masaki Hori; Anna Sótér; Vladimir I. Korobov

2014-04-30T23:59:59.000Z

110

High-resolution X-ray spectroscopy of hollow atoms created in plasma heated by subpicosecond laser radiation  

SciTech Connect (OSTI)

The investigations of ultrashort (0.4-0.6 ps) laser pulse radiation interaction with solid targets have been carried out. The Trident subpicosecond laser system was used for plasma creation. The X-ray plasma emission was investigated with the help of high-resolution spectrographs with spherically bent mica crystals. It is shown that when high contrast ultrashort laser pulses were used for plasma heating its emission spectra could not be explained in terms of commonly used theoretical models, and transitions in so called {open_quotes}hollow atoms{close_quotes} must be taken into account for adequate description of plasma radiation.

Faenov, A.Ya.; Magunov, A.I.; Pikuz, T.A. [Multicharged Ions Spectra Data Center of VNIIFTRI, Moscow (Russian Federation)] [and others

1997-10-01T23:59:59.000Z

111

Breakthrough: X-ray Laser Captures Atoms and Molecules in Action  

SciTech Connect (OSTI)

The Linac Coherent Light Source at SLAC is the world's most powerful X-ray laser. Just two years after turning on in 2009, breakthrough science is emerging from the LCLS at a rapid pace. A recent experiment used the X-rays to create and probe a 2-million-degree piece of matter in a controlled way for the first time-a significant leap toward understanding the extreme conditions found in the hearts of stars and giant planets, and a finding which could further guide research into nuclear fusion, the mechanism that powers the sun. Upcoming experiments will investigate the fundamental, atomic-scale processes behind such phenomena as superconductivity and magnetism, as well as peering into the molecular workings of photosynthesis in plants.

Bergmann, Uwe

2012-04-26T23:59:59.000Z

112

Breakthrough: X-ray Laser Captures Atoms and Molecules in Action  

ScienceCinema (OSTI)

The Linac Coherent Light Source at SLAC is the world's most powerful X-ray laser. Just two years after turning on in 2009, breakthrough science is emerging from the LCLS at a rapid pace. A recent experiment used the X-rays to create and probe a 2-million-degree piece of matter in a controlled way for the first time-a significant leap toward understanding the extreme conditions found in the hearts of stars and giant planets, and a finding which could further guide research into nuclear fusion, the mechanism that powers the sun. Upcoming experiments will investigate the fundamental, atomic-scale processes behind such phenomena as superconductivity and magnetism, as well as peering into the molecular workings of photosynthesis in plants.

Bergmann, Uwe

2014-05-21T23:59:59.000Z

113

Analysis of atomic distribution in as-fabricated Zircaloy-2 claddings by atom probe tomography under high-energy pulsed laser  

Science Journals Connector (OSTI)

Abstract The properties of second-phase particles (SPPs) in Zircaloy-2 claddings are key factors influencing the corrosion resistance of the alloy. The chemical compositions of Zr (Fe, Cr)2 and Zr2(Fe, Ni) \\{SPPs\\} were investigated by means of pulsed laser atom probe tomography. In order to prevent specimen fracture and to analyse wide regions of the specimen, the pulsed laser energy was increased to 2.0 nJ. This gave a high yield of average of 3 × 107 ions per specimen. The Zr (Fe, Cr)2 \\{SPPs\\} contained small amounts of Ni and Si atoms, while in Zr2(Fe, Ni) \\{SPPs\\} almost all the Si was concentrated and the ratio of Zr: (Fe + Ni + Si) was 2:1. Atomic concentrations of the Zr-matrix and the \\{SPPs\\} were identified by two approaches: the first by using all the visible peaks of the mass spectrum and the second using the representative peaks with the natural abundance of the corresponding atoms. It was found that the change in the concentration between the Zr-matrix and the \\{SPPs\\} can be estimated more accurately by the second method, although Sn concentration in the Zr2(Fe, Ni) \\{SPPs\\} is slightly overestimated.

T. Sawabe; T. Sonoda; S. Kitajima; T. Kameyama

2013-01-01T23:59:59.000Z

114

Role of Photoexcitation and Field Ionization in the Measurement of Accurate Oxide Stoichiometry by Laser-Assisted Atom Probe Tomography  

SciTech Connect (OSTI)

Pulsed lasers extend the high spatial and mass resolution of atom probe tomography (APT) to non-conducting materials, such as oxides. For prototypical metal oxide MgO, measured stoichiometry depends strongly upon pulse energy and applied voltage. Very low laser energies (0.02 pJ) and high electric fields yield optimal stoichiometric accuracy, attributed to the field-dependent ionization of photo-desorbed O or O2 neutrals. This emphasizes the importance of considering electronic excitations in APT analysis of oxides ionic materials.

Devaraj, Arun; Colby, Robert J.; Hess, Wayne P.; Perea, Daniel E.; Thevuthasan, Suntharampillai

2013-03-06T23:59:59.000Z

115

Clustering of metal atoms in organic media. 9. High-activity Ni/MgO catalysts prepared by metal vapor methods. Surface area and particle size effects  

SciTech Connect (OSTI)

A metal vapor method was employed to prepare highly dispersed Ni metal catalysts (solvated metal atom dispersed = SMAD catalyst) supported on MgO. Compared with conventional Ni/MgO compositions, the SMAD catalysts showed much greater activities for all reactions studied (hydrogenolysis of methylcyclopentane, MCP; hydrogenation/hydrogenolysis of toluene, TOL; methanation of carbon monoxide, CO; dehydration of isopropyl alcohol, IPA). These high activities for the SMAD catalysts are attributed to the high surface area of Ni on MgO and the high percentage of this Ni in a zero-valent state (reduction degree). Conventional methods for preparing Ni/MgO catalysts did not yield nearly such favorable surface areas or reduction degrees. Nickel particle size effects were observed during hydrogenolysis studies of MCP and hydrogenation studies of TOL. These phenomena are explained by assuming the size of an active Ni particle to be largest for hydrogenolysis of MCP > hydrogenation of TOL > methanation of CO approx. = dehydrogenation of IPA. 8 figures, 2 tables.

Matsuo, K.; Klabunde, K.J.

1982-02-01T23:59:59.000Z

116

Feasibility of UV lasing without inversion in mercury vapor  

E-Print Network [OSTI]

We investigate the feasibility of UV lasing without inversion at a wavelength of $253.7$ nm utilizing interacting dark resonances in mercury vapor. Our theoretical analysis starts with radiation damped optical Bloch equations for all relevant 13 atomic levels. These master equations are generalized by considering technical phase noise of the driving lasers. From the Doppler broadened complex susceptibility we obtain the stationary output power from semiclassical laser theory. The finite overlap of the driving Gaussian laser beams defines an ellipsoidal inhomogeneous gain distribution. Therefore, we evaluate the intra-cavity field inside a ring laser self-consistently with Fourier optics. This analysis confirms the feasibility of UV lasing and reveals its dependence on experimental parameters.

Martin R. Sturm; Benjamin Rein; Thomas Walther; Reinhold Walser

2014-06-27T23:59:59.000Z

117

Exciplex pumped alkali laser (XPAL) modeling and theory Andrew D. Palla, Joseph T. Verdeyen, and David L. Carroll  

E-Print Network [OSTI]

Exciplex pumped alkali laser (XPAL) modeling and theory Andrew D. Palla, Joseph T. Verdeyen pumped alkali laser (XPAL) system has been demonstrated in mixtures of Cs vapor, Ar, with and without ethane, by pumping Cs-Ar atomic collision pairs and subsequent dissociation of diatomic, electronically

Carroll, David L.

118

Characteristics of the 2.65 {mu}m atomic xenon laser  

SciTech Connect (OSTI)

The laser characteristics of the 2.65 {mu}m xenon laser transition are reviewed. Measured and extrapolated laser efficiency in nuclear pumped and electron beam pumped system is reported. Previous research has indicated that the reported power efficiency is between 0.1 and 2 percent.

Hebner, G.A.

1995-10-01T23:59:59.000Z

119

Atom probe tomography characterisation of a laser diode structure grown by molecular beam epitaxy  

SciTech Connect (OSTI)

Atom probe tomography (APT) has been used to achieve three-dimensional characterization of a III-nitride laser diode (LD) structure grown by molecular beam epitaxy (MBE). Four APT data sets have been obtained, with fields of view up to 400 nm in depth and 120 nm in diameter. These data sets contain material from the InGaN quantum well (QW) active region, as well as the surrounding p- and n-doped waveguide and cladding layers, enabling comprehensive study of the structure and composition of the LD structure. Two regions of the same sample, with different average indium contents (18% and 16%) in the QW region, were studied. The APT data are shown to provide easy access to the p-type dopant levels, and the composition of a thin AlGaN barrier layer. Next, the distribution of indium within the InGaN QW was analyzed, to assess any possible inhomogeneity of the distribution of indium (''indium clustering''). No evidence for a statistically significant deviation from a random distribution was found, indicating that these MBE-grown InGaN QWs do not require indium clusters for carrier localization. However, the APT data show steps in the QW interfaces, leading to well-width fluctuations, which may act to localize carriers. Additionally, the unexpected presence of a small amount (x = 0.005) of indium in a layer grown intentionally as GaN was revealed. Finally, the same statistical method applied to the QW was used to show that the indium distribution within a thick InGaN waveguide layer in the n-doped region did not show any deviation from randomness.

Bennett, Samantha E.; Humphreys, Colin J.; Oliver, Rachel A. [Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ (United Kingdom); Smeeton, Tim M.; Hooper, Stewart E.; Heffernan, Jonathan [Sharp Laboratories of Europe Limited, Edmund Halley Road, Oxford Science Park, Oxford, OX4 4GB (United Kingdom); Saxey, David W.; Smith, George D. W. [Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH (United Kingdom)

2012-03-01T23:59:59.000Z

120

Laser-based diagnostics for condensation in laser-ablated copper plasmas  

SciTech Connect (OSTI)

We are investigating the thermodynamic conditions under which condensation occurs in laser-ablated copper plasma plumes. The plasma is created by XeCl excimer laser ablation (308 nm, 350 mJ/pulse) at power densities from 500--1000 MW/cm{sup 2}. The atomic vapor expands rapidly into backing pressures of helium ranging from 0--50 torr. The backing gas serves to slow the vapor before it rarefies and provides a third body to stabilize collision complexes between vapor atoms to produce small cluster species. The formation of these small clusters is indicative of the onset of condensation, a process which, under the proper conditions, eventually forms macroscopic particulate in the plume. We use laser-induced fluorescence (LIF) to probe both atomic copper and the copper dimer molecule, Cu{sub 2}. Velocities of atomic Cu have been obtained by a time-of-flight method under varying conditions of backing gas pressure. At low pressure (10 mtorr), the atomic Cu velocity peaks at approximately 2 {times} 10{sup 6} cm/s. Excitation scans of the Cu{sub 2} A {minus} X (0,0) and (1,1) bands yield both a rotational temperature and a vibrational temperature. Direct laser beam absorption is used to determine the number density of atomic copper. Rayleigh scattering from particulate is easily observable under conditions favorable to particulate production. The Cu{sub 2} LIF and Rayleigh-scattered signals disappear instantaneously in the absence of the ablation laser pulse indicating that the particulate is formed during a single laser shot. 10 refs., 9 figs.

Sappey, A.D.; Gamble, T.K.

1991-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

High Rydberg Atoms: Newcomers to the Atomic Physics Scene  

Science Journals Connector (OSTI)

...HYDROGEN ATOM, NUCLEAR FUSION 5 : 41 ( 1965 ). BAYFIELD...HIGHLY-EXCITED KR ATOMS BY HF AND HCL MOLECULES, BULLETIN...USING A CW TUNABLE DYE LASER, PHYSICAL REVIEW LETTERS...such diverse fields as laser development, laser isotopeseparation, energy...

Ronald F. Stebbings

1976-08-13T23:59:59.000Z

122

Comparison of Laser (LMS), Californium-252 Plasma Desorption (252Cf-PDMS), Fast Atom Bombardment (FAB), Secondary Ion (SIMS), and Field Desorption (FD) Mass Spectra of a Series of Internal Salts  

Science Journals Connector (OSTI)

Comparison of the mass spectral techniques of Laser (LMS), Californium-252 Plasma Desorption (252Cf-PDMS), Secondary Ion (SIMS), Fast Atom Bombardment (FAB), and Field...

Balasanmugam, Kesagapillai; Viswanadham, Somayajula Kasi; Hercules, David M; Cotter, Robert J; Heller, David; Benninghoven, A; Sichtermann, W; Anders, V; Keough, T; Macfarlane, Ronald D; McNeal, Catherine J

1987-01-01T23:59:59.000Z

123

Large negative and positive delay of optical pulses in coherently prepared dense Rb vapor with buffer gas RID B-9041-2008  

E-Print Network [OSTI]

Large negative and positive delay of optical pulses in coherently prepared dense Rb vapor with buffer gas Eugeniy E. Mikhailov,1,2,* Vladimir A. Sautenkov,1,3 Irina Novikova,1,4 and George R. Welch1 1Department of Physics and Institute.... To prolong the interaction time, an inert buffer gas is often added to the atomic vapor to slow the diffusion of the coherently prepared atoms through the laser beam [10?12]. However, it has been recently dem- onstrated that significant modification...

Mikhailov, E. E.; Sautenkov, V. A.; Novikova, I.; Welch, George R.

2004-01-01T23:59:59.000Z

124

Intensity-resolved Above Threshold Ionization Yields of Atoms with Ultrashort Laser Pulses  

E-Print Network [OSTI]

. Electron ionization yields of xenon were measured for a set of laser pulse intensities using a time of flight (TOF) setup. Horizontally polarized, unchirped, pulses were used in the ionization process. All laser parameters other than the radiation... Tiezer, I am grateful for all their time and help. I would like to thank Dr. James Strohaber for detailed discussions and assistance related to this experiment. I acknowledge the Department of Physics at Texas A&M and the US Air Force...

Hart, Nathan Andrew

2012-10-19T23:59:59.000Z

125

Spray structures and vaporizing characteristics of a GDI fuel spray  

Science Journals Connector (OSTI)

The spray structures and distribution characteristics of liquid and vapor phases in non-evaporating and evaporating Gasoline Direct Injection (GDI) fuel sprays were investigated using Laser Induced...

Dong-Seok Choi; Gyung-Min Choi; Duck-Jool Kim

2002-07-01T23:59:59.000Z

126

Laser Desorption/Ionization of Transition Metal Atoms and Oxides from Solid Argon Lester Andrews,*, Andreas Rohrbacher, Christopher M. Laperle, and Robert E. Continetti  

E-Print Network [OSTI]

, approximately 10% of the gas sample condensed on the 10K copper plate. For ablation a focused (10 cm f of the laser-ablated metal atoms and O2 in excess argon during condensation at 10 K, have been laser desorbed spectrometry. Adding the C6H5Br chromophore to the Ar/O2 gas mixture also enhanced the metal and oxide ion

Continetti, Robert E.

127

Laser Irradiated Enhancement of the Atomic Electron Capture Rate in Search of New Physics  

Science Journals Connector (OSTI)

......Introduction Capture processes have a potential power to search for new physics. For example, instead of neutrinoless double beta decay, the process (Z, A) + e- (Z - 2, A) + e+ , (1.1) where (Z, A) denotes a nucleus of atomic......

Takaaki Nomura; Joe Sato; Takashi Shimomura

2007-03-01T23:59:59.000Z

128

E-Print Network 3.0 - atom extreme nucleus-laser Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

The most Source: Experimental High Energy Physics Collection: Plasma Physics and Fusion ; Physics 4 Optical diagnostics of cold (I'<1mK atoms in the magneto-optical trap...

129

Formation of ultracold molecules (T?200 ?K) via photoassociation in a gas of laser-cooled atoms  

Science Journals Connector (OSTI)

Publisher Summary This chapter discusses the formation of ultracold molecules—that is, at temperatures well below 1 mK, the photoassociation scheme in a sample of laser-cooled ultracold atoms is currently the best route, yielding a few millions of molecules at a translational temperature in the microkelvin range, which were successfully trapped. In photoassociation experiments, a pair of ultracold ground-state atoms absorbs a photon slightly (? a fraction of cm-1 to 1000 cm-1) red-detuned relative to the resonance line. Because of the ultracold conditions, the width of the statistical distribution of the kinetic energy Ec is markedly reduced. For a gas of atoms at thermal equilibrium with a temperature T, this width is of the order of kBT. It corresponds to ?200 cm-1 at room temperature (300 K), yielding the well-known appearance of diffuse spectra, but only to ? 2 \\{MHz\\} or 7 × 10–5 cm-1, at 100 ?K yielding well-resolved spectral lines, similar to bound–bound transitions. Besides, only a few partial waves have to be considered in the description of the initial continuum state, so the rotational structure is most often limited to J < 7–10, in contrast with conventional molecular spectra where a much larger number of rotational levels are usually observed.

Françoise Masnou-Seeuws; Pierre Pillet

2001-01-01T23:59:59.000Z

130

Threshold of a random laser based on Raman gain in cold atoms  

E-Print Network [OSTI]

," Appl. Phys. Lett. 73, 3656­3658 (1998). 5. D. S. Wiersma and S. Cavalier, "Light emission-doped nematic liquid crystals," Opt. Express 14, 7737­7744 (2006). 7. D. S. Wiersma and A. Lagendijk, "Light Interactions in Multimode Random Lasers," Science 320, 643­646 (2008). 11. D. S. Wiersma, "The physics

Kaiser, Robin

131

Laser Safety Introduction  

E-Print Network [OSTI]

Laser Safety #12;Introduction · A Laser is a device that controls the way energized atoms release photons. · LASER is an acronym for "Light Amplification by Stimulated Emission of Radiation" · The light emitted by a laser is non

McQuade, D. Tyler

132

Variable emissivity laser thermal control system  

DOE Patents [OSTI]

A laser thermal control system for a metal vapor laser maintains the wall mperature of the laser at a desired level by changing the effective emissivity of the water cooling jacket. This capability increases the overall efficiency of the laser.

Milner, Joseph R. (Livermore, CA)

1994-01-01T23:59:59.000Z

133

Effect of Surface Charge on Laser-induced Neutral Atom Desorption  

SciTech Connect (OSTI)

When an ionic metal oxide crystal is cleaved, inhomogeneous electrical charging of the surface can be a result. Such an effect has been well-documented in magnesium oxide (100). For example, recent rigorous AFM studies indicate that nanoscale charged clusters of MgO are created during cleavage, with high concentrations often located at terrace step edges.[1] In addition, ablation processes of freshly cleaved magnesium oxide crystals may be effected by remnant surface charging and microstructures.[2] We report here that such surface charging strongly impacts even neutral atom desorption, even under conditions of extremely mild excitation of surface terrace features. In our experiments, single crystal MgO (100) is cleaved in air and placed in an ultra-high vacuum chamber (UHV). We irradiate the crystal at 6.4 eV, photon energy resonant with five-coordinated (5-C) terrace sites and probe desorbing neutral oxygen atoms. It is found that a significant fraction of desorbed neutral oxygen atoms from the charged surface possess kinetic energies in excess of 0.7 eV. This is in contrast to uncharged samples (discharged in vacuo over 24 hours) that display a near-thermal oxygen atom distribution.

Beck, Kenneth M.; Joly, Alan G.; Hess, Wayne P.

2010-10-01T23:59:59.000Z

134

High passive-stability diode-laser design for use in atomic-physics experiments  

E-Print Network [OSTI]

We present the design and performance characterization of an external cavity diode-laser system optimized for high stability, low passive spectral linewidth, low cost, and ease of in-house assembly. The main cavity body is machined from a single aluminum block for robustness to temperature changes and mechanical vibrations, and features a stiff and light diffraction-grating arm to suppress low-frequency mechanical resonances. The cavity is vacuum-sealed, and a custom-molded silicone external housing further isolates the system from acoustic noise and temperature fluctuations. Beam shaping, optical isolation, and fiber coupling are integrated, and the design is easily adapted to many commonly used wavelengths. Resonance data, passive-linewidth data, and passive stability characterization of the new design demonstrate that its performance exceeds published specifications for commercial precision diode-laser systems. The design is fully documented and freely available.

Cook, Eryn C; Brown-Heft, Tobias L; Garman, Jeffrey C; Steck, Daniel A

2012-01-01T23:59:59.000Z

135

Anomalous laser-induced ionization rates of molecules and rare-gas atoms  

SciTech Connect (OSTI)

Electron tunnel ionization is considered as the mechanism for producing free electrons in gases under laser radiation. The Keldysh result and the Ammosov-Delone-Krainov (ADK) formulation are amended by considering the excess forces due to the interaction of the electric field of the laser with the electron cloud in a simple mass-on-a-spring approximation. The result of this excess force is a kinetic energy that is directed along the polarization vector of the laser field and an induced potential energy that are proposed as a determining factor in electron tunnel ionization. Relative ionization rates for various pairs of gases are calculated and compared with reported figures. Comparisons were made between several combinations of O{sub 2}, Xe, Ar, N{sub 2}, Cl{sub 2}, H{sub 2}, CO, Kr, NO, F{sub 2}, and D{sub 2}. Predicted ratios of ionization rates between pairs of gases are compared to ADK predictions. Apparently anomalous ionization rates of O{sub 2}, D{sub 2}, and H{sub 2} are explained. A simple expression is developed that reveals why the ionization rate of Xe is about an order of magnitude larger than that of O{sub 2} even though their ionization potentials are nearly identical; why CO is only about half that of Kr even though their ionization potentials are nearly the same; why the ratio of O{sub 2} to O is about ten times larger than predicted by ADK; and why the ratio of NO to Xe is about an order of magnitude less than predicted by ADK.

Bettis, Jerry Ray [5701 Woodlake Drive, Stillwater, Oklahoma 74074 (United States)

2009-12-15T23:59:59.000Z

136

Determination of transient atomic structure of laser-excited materials from time-resolved diffraction data  

SciTech Connect (OSTI)

The time evolution of the Bragg peaks of photo-excited gold nanofilms is measured using transmission ultrafast electron diffraction (UED) with 3.0 MeV electron pulses and the corresponding structure evolution is calculated using two-temperature molecular dynamics (2T-MD). The good agreement obtained between the measured and calculated Bragg peaks, over the full experimental timescale, enables the lattice temperature effects and the structural changes to be disentangled for the first time. The agreement demonstrates that 2T-MD is a reliable method for solving the inverse problem of structure determination of laser irradiated metals in UED measurements.

Giret, Yvelin [The Institute of Scientific and Industrial Research (ISIR), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047 (Japan) [The Institute of Scientific and Industrial Research (ISIR), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047 (Japan); Department of Physics and Astronomy, University College London, Gower Street, WC1E 6BT London (United Kingdom); Naruse, Nobuyasu; Murooka, Yoshie; Yang, Jinfeng; Tanimura, Katsumi [The Institute of Scientific and Industrial Research (ISIR), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047 (Japan)] [The Institute of Scientific and Industrial Research (ISIR), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047 (Japan); Daraszewicz, Szymon L.; Duffy, Dorothy M.; Shluger, Alexander L. [Department of Physics and Astronomy, University College London, Gower Street, WC1E 6BT London (United Kingdom)] [Department of Physics and Astronomy, University College London, Gower Street, WC1E 6BT London (United Kingdom)

2013-12-16T23:59:59.000Z

137

One-atom correlated-emission laser RID C-6638-2008  

E-Print Network [OSTI]

of interest in quantum optics. In the last decade there have been many theoretical proposals #3;1?5#4; as well as experimental demon- stration #3;6?8#4; for the realizing of such a device. These ex- periments have utilized a beam of atoms in such a way... the transi- tions #5;a#6;? #5;c#6; and #5;b#6;? #5;d#6;, with transition frequencies la- beled as wac and wbd, interact with the cavity mode having coupling constant g1 and g2. These two transitions have de- tuning #3;2=v2?wac and #3;4=v4?wbd...

Kim, Ho-Joon; Khosa, Ashfaq H.; Lee, Hai-Woong; Zubairy, M. Suhail

2008-01-01T23:59:59.000Z

138

Sub-Doppler resonances in the back-scattered light from random porous media infused with Rb vapor  

E-Print Network [OSTI]

We report on the observation of sub-Doppler resonances on the back-scattered light from a random porous glass medium with rubidium vapor filling its interstices. The sub-Doppler spectral lines are the consequence of saturated absorption where the incident laser beam saturates the atomic medium and the back-scattered light probes it. Some specificities of the observed spectra reflect the transient atomic evolution under confinement inside the pores. Simplicity, robustness and potential miniaturization are appealing features of this system as a spectroscopic reference.

Villalba, S; Lenci, L; Bloch, D; Lezama, A; Failache, H

2013-01-01T23:59:59.000Z

139

Safety approaches for high power modular laser operation  

SciTech Connect (OSTI)

Approximately 20 years ago, a program was initiated at the Lawrence Livermore National Laboratory (LLNL) to study the feasibility of using lasers to separate isotopes of uranium and other materials. Of particular interest has been the development of a uranium enrichment method for the production of commercial nuclear power reactor fuel to replace current more expensive methods. The Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) Program has progressed to the point where a plant-scale facility to demonstrate commercial feasibility has been built and is being tested. The U-AVLIS Program uses copper vapor lasers which pump frequency selective dye lasers to photoionize uranium vapor produced by an electron beam. The selectively ionized isotopes are electrostatically collected. The copper lasers are arranged in oscillator/amplifier chains. The current configuration consists of 12 chains, each with a nominal output of 800 W for a system output in excess of 9 kW. The system requirements are for continuous operation (24 h a day, 7 days a week) and high availability. To meet these requirements, the lasers are designed in a modular form allowing for rapid change-out of the lasers requiring maintenance. Since beginning operation in early 1985, the copper lasers have accumulated over 2 million unit hours at a >90% availability. The dye laser system provides approximately 2.5 kW average power in the visible wavelength range. This large-scale laser system has many safety considerations, including high-power laser beams, high voltage, and large quantities ({approximately}3000 gal) of ethanol dye solutions. The Laboratory`s safety policy requires that safety controls be designed into any process, equipment, or apparatus in the form of engineering controls. Administrative controls further reduce the risk to an acceptable level. Selected examples of engineering and administrative controls currently being used in the U-AVLIS Program are described.

Handren, R.T.

1993-03-01T23:59:59.000Z

140

Optical atomic magnetometer  

DOE Patents [OSTI]

An optical atomic magnetometers is provided operating on the principles of nonlinear magneto-optical rotation. An atomic vapor is optically pumped using linearly polarized modulated light. The vapor is then probed using a non-modulated linearly polarized light beam. The resulting modulation in polarization angle of the probe light is detected and used in a feedback loop to induce self-oscillation at the resonant frequency.

Budker, Dmitry; Higbie, James; Corsini, Eric P

2013-11-19T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Doppler- and recoil-free laser excitation of Rydberg states via three-photon transitions  

SciTech Connect (OSTI)

Three-photon laser excitation of Rydberg states by three different laser beams can be arranged in a starlike geometry that simultaneously eliminates the recoil effect and Doppler broadening. Our analytical and numerical calculations for a particular laser excitation scheme 5S{sub 1/2}{yields}5P{sub 3/2}{yields}6S{sub 1/2}{yields}nP in Rb atoms have shown that, compared to the one- and two-photon laser excitation, this approach provides much narrower linewidth and longer coherence time for both cold atom samples and hot vapors, if the intermediate one-photon resonances of the three-photon transition are detuned by more than respective single-photon Doppler widths. This method can be used to improve fidelity of Rydberg quantum gates and precision of spectroscopic measurements in Rydberg atoms.

Ryabtsev, I. I.; Beterov, I. I.; Tretyakov, D. B.; Entin, V. M.; Yakshina, E. A. [A. V. Rzhanov Institute of Semiconductor Physics SB RAS, Prospekt Lavrentyeva 13, 630090 Novosibirsk (Russian Federation)

2011-11-15T23:59:59.000Z

142

Observation of prolonged coherence time of the collective spin wave of an atomic ensemble in a paraffin-coated {sup 87}Rb vapor cell  

SciTech Connect (OSTI)

We report a prolonged coherence time of the collective spin wave of a thermal {sup 87}Rb atomic ensemble in a paraffin-coated cell. The spin wave is prepared through a stimulated Raman process. The long coherence time is achieved by prolonging the lifetime of the spins with paraffin coating and minimize dephasing with optimal experimental configuration. The observation of the long-time-delayed-stimulated Stokes signal in the writing process suggests the prolonged lifetime of the prepared spins; a direct measurement of the decay of anti-Stokes signal in the reading process shows the coherence time is up to 300 mus after minimizing dephasing. This is 100 times longer than the reported coherence time in the similar experiments in thermal atomic ensembles based on the Duan-Lukin-Cirac-Zoller and its improved protocols. This prolonged coherence time sets the upper limit of the memory time in quantum repeaters based on such protocols, which is crucial for the realization of long-distance quantum communication. The previous reported fluorescence background in the writing process due to collision in a sample cell with buffer gas is also reduced in a cell without buffer gas.

Jiang Shuo; Luo Xiaoming; Chen Liqing; Ning Bo [Physics Department, Tsinghua University, Beijing 100084 (China); Chen Shuai [Physikalisches Institute, Universitaet Heidelberg, 69120 Heidelberg (Germany); Wang Jingyang; Zhong Zhiping [College of Physical Sciences, Graduate University of the Chinese Academy of Sciences, P.O. Box 4588, Beijing 100049 (China); Pan Jianwei [Physics Department, Tsinghua University, Beijing 100084 (China); Physikalisches Institute, Universitaet Heidelberg, 69120 Heidelberg (Germany)

2009-12-15T23:59:59.000Z

143

The Laser as a Weapon  

Science Journals Connector (OSTI)

The laser beam is popularly thought of as a very powerful death ray which can be fired from a hand-held laser gun to vaporize soldiers, demolish buildings, and burn through tanks. This is an immense exaggeration ...

Major General Bengt Anderberg; Dr. Myron L. Wolbarsht

1992-01-01T23:59:59.000Z

144

Charge steering of laser plasma accelerated fast ions in a liquid spray — creation of MeV negative ion and neutral atom beams  

SciTech Connect (OSTI)

The scenario of “electron capture and loss” has been recently proposed for the formation of negative ion and neutral atom beams with up to MeV kinetic energy [S. Ter-Avetisyan, et al., Appl. Phys. Lett. 99, 051501 (2011)]. Validation of these processes and of their generic nature is here provided in experiments where the ion source and the interaction medium have been spatially separated. Fast positive ions accelerated from a laser plasma source are sent through a cold spray where their charge is changed. Such formed neutral atom or negative ion has nearly the same momentum as the original positive ion. Experiments are released for protons, carbon, and oxygen ions and corresponding beams of negative ions and neutral atoms have been obtained. The electron capture and loss phenomenon is confirmed to be the origin of the negative ion and neutral atom beams. The equilibrium ratios of different charge components and cross sections have been measured. Our method is general and allows the creation of beams of neutral atoms and negative ions for different species which inherit the characteristics of the positive ion source.

Schnürer, M.; Abicht, F.; Priebe, G.; Braenzel, J. [Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin (Germany)] [Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin (Germany); Prasad, R. [Institute for Laser and Plasma Physics, Heinrich Heine University, Duesseldorf 40225 (Germany)] [Institute for Laser and Plasma Physics, Heinrich Heine University, Duesseldorf 40225 (Germany); Borghesi, M. [School of Mathematics and Physics, The Queen's University of Belfast, Belfast BT7 1NN (United Kingdom) [School of Mathematics and Physics, The Queen's University of Belfast, Belfast BT7 1NN (United Kingdom); ELI–Beamlines, Institute of Physics, Czech Academy of Science, 18221 Prague (Czech Republic); Andreev, A. [Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin (Germany) [Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin (Germany); Vavilov State Optical Institute, 119034 St. Petersburg (Russian Federation); Nickles, P. V. [WCU Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Gwangju (Korea, Republic of)] [WCU Department of Nanobio Materials and Electronics, Gwangju Institute of Science and Technology, Gwangju (Korea, Republic of); Jequier, S.; Tikhonchuk, V. [Centre Lasers Intenses et Applications, University of Bordeaux, CEA, CNRS, 33405 Talence (France)] [Centre Lasers Intenses et Applications, University of Bordeaux, CEA, CNRS, 33405 Talence (France); Ter-Avetisyan, S. [ELI–Beamlines, Institute of Physics, Czech Academy of Science, 18221 Prague (Czech Republic)] [ELI–Beamlines, Institute of Physics, Czech Academy of Science, 18221 Prague (Czech Republic)

2013-11-15T23:59:59.000Z

145

Laser-induced breakdown spectroscopy (LIBS): a new spectrochemical technique  

SciTech Connect (OSTI)

We have used the breakdown spark from a focused laser beam to generate analytically useful emission spectra of minor constituents in air and other carrier gases. The medium was sampled directly. It was not necessary to reduce the sample to solution nor to introduce electrodes. The apparatus is particularly simple; a pulsed laser, spectrometer, and some method for time resolution. The latter is essential in laser-induced-breakdown spectroscopy (LIBS) because of the strong early continuum. High temperatures in the spark result in vaporization of small particles, dissociation of molecules, and excitation of atomic and ionic spectra, including species which are normally difficult to detect. In one application, we have monitored beryllium in air at conventrations below 1 ..mu..g/m/sup 3/, which is below 1 ppB (w/w). In another we have monitored chlorine and fluorine atoms in real time. LIBS has the potential for real-time direct sampling of contaminants in situ.

Radziemski, L.J.; Loree, T.R.; Cremers, D.A.

1982-01-01T23:59:59.000Z

146

Laser manipulation of atoms  

Science Journals Connector (OSTI)

... with the Ne+ (3S-3P) transition is sufficient to cause observable slowing (E. Riis, University of Aarhus). Calculations show that an ion beam circulating in a storage ...

A. Ashkin

1987-12-23T23:59:59.000Z

147

Calibrated vapor generator source  

DOE Patents [OSTI]

A portable vapor generator is disclosed that can provide a controlled source of chemical vapors, such as, narcotic or explosive vapors. This source can be used to test and calibrate various types of vapor detection systems by providing a known amount of vapors to the system. The vapor generator is calibrated using a reference ion mobility spectrometer. A method of providing this vapor is described, as follows: explosive or narcotic is deposited on quartz wool, placed in a chamber that can be heated or cooled (depending on the vapor pressure of the material) to control the concentration of vapors in the reservoir. A controlled flow of air is pulsed over the quartz wool releasing a preset quantity of vapors at the outlet. 10 figs.

Davies, J.P.; Larson, R.A.; Goodrich, L.D.; Hall, H.J.; Stoddard, B.D.; Davis, S.G.; Kaser, T.G.; Conrad, F.J.

1995-09-26T23:59:59.000Z

148

Optical Precursors in Rubidium Vapor and Their Relation to Superradiance  

E-Print Network [OSTI]

Optical precursor is the sharp optical pulse front that does not show delay in absorptive media. In this thesis, optical precursor behavior in rubidium (Rb) vapor was investigated in the picoseconds regime. An amplified femtosecond laser was shaped...

Yang, Wenlong

2012-10-19T23:59:59.000Z

149

Polycrystalline silicon resistor trimming by laser annealing  

E-Print Network [OSTI]

. Measuring Hall mobility with the van der Pauw pattern. Hall mobility measurexaent station. 41 41 43 45 45 CHAPTER I INTRODUCTION Lasers have been used to trim analog and analog/digital integrated circuits (IC's) since the late 1960's [1] ? [3... by pyrolytic decomposition of silane gas (SiH4) into silicon atoms and hydrogen gas [22] SiH4 ~ Si + 2Hs. This chemical vapor deposition (CVD) process can be performed at atmospheric pressure or low pressure. The substrate is maintained at an elevated...

Crowley, Robert Terrence

1989-01-01T23:59:59.000Z

150

Atomic magnetometer  

DOE Patents [OSTI]

An atomic magnetometer is disclosed which uses a pump light beam at a D1 or D2 transition of an alkali metal vapor to magnetically polarize the vapor in a heated cell, and a probe light beam at a different D2 or D1 transition to sense the magnetic field via a polarization rotation of the probe light beam. The pump and probe light beams are both directed along substantially the same optical path through an optical waveplate and through the heated cell to an optical filter which blocks the pump light beam while transmitting the probe light beam to one or more photodetectors which generate electrical signals to sense the magnetic field. The optical waveplate functions as a quarter waveplate to circularly polarize the pump light beam, and as a half waveplate to maintain the probe light beam linearly polarized.

Schwindt, Peter (Albuquerque, NM); Johnson, Cort N. (Albuquerque, NM)

2012-07-03T23:59:59.000Z

151

Cavity induced modifications to the resonance fluorescence and probe absorption of a laser-dressed V atom  

E-Print Network [OSTI]

A cavity-modified master equation is derived for a coherently driven, V-type three-level atom coupled to a single-mode cavity in the bad cavity limit. We show that population inversion in both the bare and dressed-state bases may be achieved, originating from the enhancement of the atom-cavity interaction when the cavity is resonant with an atomic dressed-state transition. The atomic populations in the dressed state representation are analysed in terms of the cavity-modified transition rates. The atomic fluorescence spectrum and probe absorption spectrum also investigated, and it is found that the spectral profiles may be controlled by adjusting the cavity frequency. Peak suppression and line narrowing occur under appropriate conditions.

Jin-Sheng Peng; Gao-Xiang Li; Peng Zhou; S. Swain

2000-03-20T23:59:59.000Z

152

Recent Progress in ultracold atoms  

E-Print Network [OSTI]

and Einstein What is Bose-Einstein condensation (BEC)? #12;300 K to 1 mK 109 atoms 1 mK to 1 mK 108 106 atoms How to make a BEC: Cool atoms at ultra low temperature Laser beams Fluorescence Laser cooling (Doppler

Baltisberger, Jay H.

153

ARM Water Vapor IOP  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ARM Water Vapor IOP The SGP CART site will host the third ARM water vapor IOP on September 18-October 8, 2000. The CART site is home to a powerful array of instruments capable of...

154

Experimental studies of electron impact depopulation of excited states of atoms: applications to laser development for fusion and isotope separation. Final report, 1 January 1977-30 June 1979  

SciTech Connect (OSTI)

Motivated by the need for measurements of metastable depopulation mechanisms of Ar and Kr in the KrF rare-gas monohalide excimer laser, an ultra-high vacuum triple crossed-beams apparatus has been designed, fabricated, and assembled for the purpose of studying electron scattering from excited states of Ar and Kr atoms. A beam of metastable rare gas atoms, produced by near-resonant charge transfer of rare gas ions with alkali neutral atoms, is crossed by an electron beam and a far-red laser beam along mutually orthogonal axes. A hemispherical electron monochromator-spectrometer pair is used to measure the cross section for electron scattering from the 2p/sub 9/ excited state of the rare gas atom. Testing of parts of the assembled apparatus has been completed.

Lubell, M.S.

1980-06-01T23:59:59.000Z

155

Laser frequency stabilization to excited state transitions using electromagnetically induced transparency in a cascade system  

SciTech Connect (OSTI)

We demonstrate laser frequency stabilization to excited state transitions using cascade electromagnetically induced transparency. Using a room temperature Rb vapor cell as a reference, we stabilize a first diode laser to the D{sub 2} transition and a second laser to a transition from the intermediate 5P{sub 3/2} state to a highly excited state with principal quantum number n=19-70. A combined laser linewidth of 280{+-}50 kHz over a 100 {mu}s time period is achieved. This method may be applied generally to any cascade system and allows laser stabilization to an atomic reference in the absence of a direct absorption signal.

Abel, R. P.; Mohapatra, A. K.; Bason, M. G.; Pritchard, J. D.; Weatherill, K. J.; Raitzsch, U.; Adams, C. S. [Department of Physics, Durham University, Rochester Building, South Road, Durham DH1 3LE (United Kingdom)

2009-02-16T23:59:59.000Z

156

Laser assisted charge transfer reactions in slow ion–atom collisions: Coupled dressed quasimolecular?states approach  

E-Print Network [OSTI]

d i a b a t i c equations which offer computational advantage. The method is illustrated by a case study of the laser assisted charge exchange process He+ ++H(1s)+???He+(n=2)+H+, in a two?state approximation, for the velocity range from 1.5×105 to 2...

Chu, Shih-I; Ho, TakSan; Laughlin, Cecil

1984-03-01T23:59:59.000Z

157

Ignition and combustion drive by powerful laser radiation acting on a water surface  

Science Journals Connector (OSTI)

The ignition and combustion effects in water vapor generated...2-laser radiation on a water surface are investigated...

G. I. Kozlov; V. A. Kuznetsov

158

E-Print Network 3.0 - atomic absorption spectroscopy Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Such powers are sufficient for laser atomic absorption spectrometry (LAAS... in graphite tube atomizers and analytical flames by wavelength modulation-laser ... Source: Ecole...

159

E-Print Network 3.0 - atomic beam frequency Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

laser and characterization of the atomic beam... is to measure the frequency dependent absorption of a laser beam intersecting the atomic beam. Depending... the ... Source:...

160

Two-mode single-atom laser as a source of entangled light RID A-5077-2009  

E-Print Network [OSTI]

.evers@mpi-hd.mpg.de ?Electronic address: keitel@mpi-hd.mpg.de PHYSICAL REVIEW A 75, 033816 #1;2007#2; 1050-2947/2007/75#1;3#2;/033816#1;8#2; 2007 The American Physical Society033816-1 the atomic transition #5;a#6;? #5;c#6;, and the second mode with frequency #1;2 interacts... with the atom on the #5;b#6;? #5;d#6; transi- tion. In the rotating-wave approximation, the interaction of the atom with the cavity modes is described by the Hamil- tonian HC = #2;g1a1#5;a#6;#7;c#5; + #2;g2a2#5;b#6;#7;d#5; + H.c. #1;1#2; Here aj #1;aj?#2...

Kiffner, M.; Zubairy, M. Suhail; Evers, J.; Keitel, C. H.

2007-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Raman-shifted KrF laser radiation with low amplified spontaneous emission for a rotational Raman daytime-temperature lidar  

SciTech Connect (OSTI)

Various configurations of a tunable two-stage KrF laser have been investigated for providing powerful laser pulses with very low amplified spontaneous emission (ASE). The lowest fraction (0.00017%) of ASE was attained with a single-pass amplifier and a phase-conjugate Brillouin mirror. The most suitable application envisaged for the laser source, i.e., remote daytime-temperature measurement by means of rotational Raman scattering, is a dedicated oscillator--amplifier configuration with an ASE of 0.005% at an output of 300 mJ. The very low values of ASE were measured with the aid of a thallium atomic-vapor filter.

Luckow, F.; Voss, E.; Zeyn, J.; Lahmann, W.; Weitkamp, C.; Michaelis, W. (Institut fuer Physik, GKSS-Forschungszentrum Geesthacht GmbH, D-21502 Geesthacht (Germany))

1994-07-15T23:59:59.000Z

162

Extracting atoms on demand with lasers Bernd Mohring,* Marc Bienert, Florian Haug, Giovanna Morigi, and Wolfgang P. Schleich  

E-Print Network [OSTI]

, into the collective quantum state of the steep trap with high efficiency in the parameter regime of present that in this setup a predetermined number of atoms can be transferred from a reservoir, a Bose-Einstein condensate exploited tunneling from a condensate to a moving quantum dot in order to re- alize this scenario 8

Raizen, Mark G.

163

Continuous-wave laser oscillation on the 1315 nm transition of atomic iodine pumped by O2,,a1  

E-Print Network [OSTI]

diagram of the flow tube setup is shown in Fig. 1. A radio-frequency rf electric discharge at 13.56 MHz nm transition of atomic iodine where the O2 a1 used to pump the iodine was produced by a radio-frequency operating between two internal hollow cathode electrodes was used as the excitation source. The plasma zone

Carroll, David L.

164

IPredictions for gain in the fission-fragment-excited atomic xenon laser Jong W. Shon and Mark J. Kushnera)  

E-Print Network [OSTI]

, New Mexico 87185 (Received 30 June 1992; accepted for publication 1 December 1992) The infrared atomic-power deposition (l-100 W cm-s), long pulse lengths (I-10 ms), and high-energy deposition (100s J 8-l). Optical responsible for this behavior. I. INTRODUCTION During the past few years, there has been a renewed interest

Kushner, Mark

165

Sequential ionization and energy gain of bound electrons in classical modeling of atoms in strong laser fields  

Science Journals Connector (OSTI)

Classical mechanics and classical ensembles have provided numerous insights into the dynamics of strong-field double ionization. In this paper, we show that in classical multidimensional modeling, the laser intensity at which sequential ionization begins to dominate depends on the softening of the interaction between the electron and nucleus. We show that an unsoftened interaction in two or three dimensions can lead to classical orbits in which an electron can start deep in the nuclear potential-energy well, gain energy from the oscillating laser field, and ionize over the barrier without any recollision. We discuss how this energy gain occurs, with the electron orbit favoring one side of the nucleus or the other, depending on which side corresponds with the rising potential-energy curve.

S. L. Haan; N. A. Danks; K. N. Shomsky

2012-09-18T23:59:59.000Z

166

Infrared Spectra of M-?2-C2H2, HM–C?CH, and HM–C?CH– Prepared in Reactions of Laser-Ablated Group 3 Metal Atoms with Acetylene  

Science Journals Connector (OSTI)

The major HM–C?CH and M-?2-C2H2 products are observed in the matrix infrared spectra from reactions of laser-ablated group 3 metal atoms with acetylene, while the vinylidene product is not detected. These results reveal that coordination of group 3 metal ...

Han-Gook Cho; Lester Andrews

2012-09-25T23:59:59.000Z

167

Vapor spill monitoring method  

DOE Patents [OSTI]

Method for continuous sampling of liquified natural gas effluent from a spill pipe, vaporizing the cold liquified natural gas, and feeding the vaporized gas into an infrared detector to measure the gas composition. The apparatus utilizes a probe having an inner channel for receiving samples of liquified natural gas and a surrounding water jacket through which warm water is flowed to flash vaporize the liquified natural gas.

Bianchini, Gregory M. (Livermore, CA); McRae, Thomas G. (Livermore, CA)

1985-01-01T23:59:59.000Z

168

ARM - Water Vapor  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Water Vapor Outreach Home Room News Publications Traditional Knowledge Kiosks Barrow, Alaska Tropical Western Pacific Site Tours Contacts Students Study Hall About ARM Global...

169

Laser cooling with ultrafast pulse trains  

E-Print Network [OSTI]

We propose a new laser cooling method for atomic species whose level structure makes traditional laser cooling difficult. For instance, laser cooling of hydrogen requires vacuum-ultraviolet laser light, while multielectron atoms need laser light at many widely separated frequencies. These restrictions can be eased by laser cooling on two-photon transitions with ultrafast pulse trains. Laser cooling of hydrogen, antihydrogen, and carbon appears feasible, and extension of the technique to molecules may be possible.

David Kielpinski

2003-06-14T23:59:59.000Z

170

Population distributions in Li vapor excited by a photoionization electron source  

Science Journals Connector (OSTI)

A detailed theoretical and experimental investigation is presented of the excited-level population distribution in a Li-Ne vapor under excitation by a photoionization electron source. This source produces a subnanosecond burst of hot (Te?20 eV) electrons with a peak density in excess of 5×1015 cm-3. The electrons are generated as a result of photoionization of Ne atoms by x rays emitted from a plasma produced by a 100-mJ laser pulse of 600 ps duration. Measurements of Li(1s22p)-atom density, and of electron density, have been performed with subnanosecond time resolution under various conditions of excitation. A comprehensive rate-equation model is described and its predictions are seen to be in good agreement with experiment. It is shown that the population distribution in the Li-Ne vapor is strongly influenced by recombination. Under the conditions of these experiments, rates for this process as high as 3×109 s-1 were observed.

R. G. Caro and J. C. Wang

1986-04-01T23:59:59.000Z

171

Accelerated guided atomic pulse  

Science Journals Connector (OSTI)

The deleterious effects of dispersion on a propagating coherent atomic pulse, along the axis of a traveling-wave laser beam, can be ameliorated by the nonlinear self-interacting force due to dipole-dipole coupling between atoms. We show that a wide atomic pulse with a particular profile can retain its shape during propagation and, moreover, the momentum of the pulse increases due to photon absorption. For the wide soliton case, we demonstrate analytically that the self-interacting atomic force scales inversely with the third power of the pulse width.

S. Dyrting; Weiping Zhang; B. C. Sanders

1997-09-01T23:59:59.000Z

172

Gasoline vapor recovery  

SciTech Connect (OSTI)

In a gasoline distribution network wherein gasoline is drawn from a gasoline storage tank and pumped into individual vehicles and wherein the gasoline storage tank is refilled periodically from a gasoline tanker truck, a method of recovering liquid gasoline from gasoline vapor that collects in the headspace of the gasoline storage tank as the liquid gasoline is drawn therefrom, said method comprising the steps of: (a) providing a source of inert gas; (b) introducing inert gas into the gasoline storage tank as liquid gasoline is drawn therefrom so that liquid gasoline drawn from the tank is displaced by inert gas and gasoline vapor mixes with the inert gas in the headspace of the tank; (c) collecting the inert gas/gasoline vapor mixture from the headspace of the gasoline storage tank as the tank is refilled from a gasoline tanker truck; (d) cooling the inert gas/gasoline vapor mixture to a temperature sufficient to condense the gasoline vapor in the mixture to liquid gasoline but not sufficient to liquify the inert gas in the mixture; (e) separating the condensed liquid gasoline from the inert gas; and delivering the condensed liquid gasoline to a remote location for subsequent use.

Lievens, G.; Tiberi, T.P.

1993-06-22T23:59:59.000Z

173

A Mass Spectrometry Study of Isotope Separation in the Laser Plume  

E-Print Network [OSTI]

1.4.2 Atomic Absorption5.3.2 Atomic Absorption Spectrometry . . . . . . . . . . .ablation and diode laser-atomic absorption spectrometry”,

Suen, Timothy Wu

2012-01-01T23:59:59.000Z

174

Electrolyte vapor condenser  

DOE Patents [OSTI]

A system is disclosed for removing electrolyte from a fuel cell gas stream. The gas stream containing electrolyte vapor is supercooled utilizing conventional heat exchangers and the thus supercooled gas stream is passed over high surface area passive condensers. The condensed electrolyte is then drained from the condenser and the remainder of the gas stream passed on. The system is particularly useful for electrolytes such as phosphoric acid and molten carbonate, but can be used for other electrolyte cells and simple vapor separation as well. 3 figs.

Sederquist, R.A.; Szydlowski, D.F.; Sawyer, R.D.

1983-02-08T23:59:59.000Z

175

Electrolyte vapor condenser  

DOE Patents [OSTI]

A system is disclosed for removing electrolyte from a fuel cell gas stream. The gas stream containing electrolyte vapor is supercooled utilizing conventional heat exchangers and the thus supercooled gas stream is passed over high surface area passive condensers. The condensed electrolyte is then drained from the condenser and the remainder of the gas stream passed on. The system is particularly useful for electrolytes such as phosphoric acid and molten carbonate, but can be used for other electrolyte cells and simple vapor separation as well.

Sederquist, Richard A. (Newington, CT); Szydlowski, Donald F. (East Hartford, CT); Sawyer, Richard D. (Canton, CT)

1983-01-01T23:59:59.000Z

176

Advances in Laser Science-II  

SciTech Connect (OSTI)

The meeting covered topics on the latest advances in laser technology and applications. The general categories are as follows: advanced lasers and coherent sources; nonlinear optical phenomena and applications; atomic, molecular and ionic spectroscopy; condensed matter, surface and particle spectroscopy; laser photochemistry and photophysics; diagnostic and analytical applications of lasers; and laser research and techniques in medicine and biology. (LSP)

Lapp, M.; Stwalley, W.C.; Kenney-Wallace, G.A.; Lerner, R.G. (eds.)

1987-01-01T23:59:59.000Z

177

RICE UNIVERSITY Ultracold Collisions in Atomic Strontium  

E-Print Network [OSTI]

RICE UNIVERSITY Ultracold Collisions in Atomic Strontium by Sarah B. Nagel A Thesis Submitted Houston, Texas February, 2008 #12;Abstract Ultracold Collisions in Atomic Strontium by Sarah B. Nagel In this work with atomic Strontium, the atoms are first laser cooled and subse- quently trapped, in a MOT

Killian, Thomas C.

178

Organic vapor jet printing system  

SciTech Connect (OSTI)

An organic vapor jet printing system includes a pump for increasing the pressure of an organic flux.

Forrest, Stephen R

2012-10-23T23:59:59.000Z

179

Analysis of two-dimensional high-energy photoelectron momentum distributions in the single ionization of atoms by intense laser pulses  

E-Print Network [OSTI]

, using longer pulses at lower intensities. The energy spectra above 4Up, where Up is the ponderomotive energy, have been found to vary rapidly with small changes in laser intensities 10,11 when laser pulseAnalysis of two-dimensional high-energy photoelectron momentum distributions in the single

Lin, Chii-Dong

180

Mercury Vapor | Open Energy Information  

Open Energy Info (EERE)

Mercury Vapor Mercury Vapor Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Mercury Vapor Details Activities (23) Areas (23) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Fluid Lab Analysis Parent Exploration Technique: Fluid Lab Analysis Information Provided by Technique Lithology: Stratigraphic/Structural: Anomalously high concentrations can indicate high permeability or conduit for fluid flow Hydrological: Field wide soil sampling can generate a geometrical approximation of fluid circulation Thermal: High concentration in soils can be indicative of active hydrothermal activity Dictionary.png Mercury Vapor: Mercury is discharged as a highly volatile vapor during hydrothermal

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Stratified vapor generator  

DOE Patents [OSTI]

A stratified vapor generator (110) comprises a first heating section (H.sub.1) and a second heating section (H.sub.2). The first and second heating sections (H.sub.1, H.sub.2) are arranged so that the inlet of the second heating section (H.sub.2) is operatively associated with the outlet of the first heating section (H.sub.1). A moisture separator (126) having a vapor outlet (164) and a liquid outlet (144) is operatively associated with the outlet (124) of the second heating section (H.sub.2). A cooling section (C.sub.1) is operatively associated with the liquid outlet (144) of the moisture separator (126) and includes an outlet that is operatively associated with the inlet of the second heating section (H.sub.2).

Bharathan, Desikan (Lakewood, CO); Hassani, Vahab (Golden, CO)

2008-05-20T23:59:59.000Z

182

Laser Roadshow  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

outreach Laser Roadshow The NIF Laser Roadshow includes a number of interactive laser demonstrations (Laser Light Fountain, Laser DJ, and NIF "3D ride") that have traveled across...

183

E-Print Network 3.0 - atomic nuclei poisk Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Institute Collection: Physics 88 Fast Ignition: Nuclear Fusion with UltraFast Ignition: Nuclear Fusion with Ultra--intenseintense LASERsLASERs Summary: core Atomic nuclei are...

184

Laser removal of sludge from steam generators  

DOE Patents [OSTI]

A method of removing unwanted chemical deposits known as sludge from the metal surfaces of steam generators with laser energy is provided. Laser energy of a certain power density, of a critical wavelength and frequency, is intermittently focused on the sludge deposits to vaporize them so that the surfaces are cleaned without affecting the metal surface (sludge substrate). Fiberoptic tubes are utilized for laser beam transmission and beam direction. Fiberoptics are also utilized to monitor laser operation and sludge removal.

Nachbar, Henry D. (Ballston Lake, NY)

1990-01-01T23:59:59.000Z

185

The {sup 2}P{sub 1/2} {yields} {sup 2}P{sub 3/2} laser transition in atomic iodine and the problem of search for signals from extraterrestrial intelligence  

SciTech Connect (OSTI)

It is proposed to search for signals from extraterrestrial intelligence (ETI) at a wavelength of 1.315 {mu}m of the laser {sup 2}P{sub 1/2} {yields} {sup 2}P{sub 3/2} transition in the atomic iodine, which can be used for this purpose as the natural frequency reference. The search at this wavelength is promising because active quantum filters (AQFs) with the quantum sensitivity limit have been developed for this wavelength, which are capable of receiving laser signals, consisting of only a few photons, against the background of emission from a star under study. In addition, high-power iodine lasers emitting diffraction-limited radiation at 1.315 {mu}m have been created, which highly developed ETI also can have. If a ETI sends in our direction a diffraction-limited 10-ns, 1-kJ laser pulse with the beam diameter of 10 m, a receiver with an AQF mounted on a ten-meter extra-atmospheric optical telescope can detect this signal at a distance of up to 300 light years, irrespective of the ETI position on the celestial sphere. The realisation of the projects for manufacturing optical telescopes of diameter 30 m will increase the research range up to 2700 light years. A weak absorption of the 1.315-{mu}m radiation in the Earth atmosphere (the signal is attenuated by less than 20%) allows the search for ETI signals by using ground telescopes equipped with adaptive optical systems. (laser applications and other topics in quantum electronics)

Kutaev, Yu F; Mankevich, S K ['Astrofizika' Research and Production Association (Russian Federation); Nosach, O Yu; Orlov, E P [P.N. Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2007-07-31T23:59:59.000Z

186

Vapor Barriers or Vapor Diffusion Retarders | Department of Energy  

Broader source: Energy.gov (indexed) [DOE]

Home Air Sealing for New Home Construction Insulation Types of Insulation Insulation and Air Sealing Products and Services External Resources Find a Local AirVapor Barrier...

187

E-Print Network 3.0 - atomic kitteni lauljatar Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

on ultralow-temperature plasmas created from laser- cooled atoms are unleashing a flood of new ideas in atomic... and trapping has enabled enormous advances in the...

188

E-Print Network 3.0 - atomic spectroscopic detection Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

atomic flux measurement of electron-beam evaporated yttrium with a diode-laser-based atomic absorption monitor at 668 nm Summary: . The spectroscopic technique, based on...

189

E-Print Network 3.0 - analytical atomic spectrometry Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Summary: in graphite tube atomizers and analytical flames by wavelength modulation-laser atomic absorption spectrometry... down to about 310 nm. Such powers are sufficient for...

190

E-Print Network 3.0 - atom re-evaporation method Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

method Page: << < 1 2 3 4 5 > >> 1 Atomic flux measurement by diode-laser-based atomic absorption spectroscopy Summary: in the absorp- tion profile indicates that barium...

191

Effects of Laser Energy and Wavelength on the Analysis of LiFePO4...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Energy and Wavelength on the Analysis of LiFePO4 Using Laser Assisted Atom Probe Tomography. Effects of Laser Energy and Wavelength on the Analysis of LiFePO4 Using Laser...

192

Vapor spill pipe monitor  

DOE Patents [OSTI]

The invention is a method and apparatus for continually monitoring the composition of liquefied natural gas flowing from a spill pipe during a spill test by continually removing a sample of the LNG by means of a probe, gasifying the LNG in the probe, and sending the vaporized LNG to a remote ir gas detector for analysis. The probe comprises three spaced concentric tubes surrounded by a water jacket which communicates with a flow channel defined between the inner and middle, and middle and outer tubes. The inner tube is connected to a pump for providing suction, and the probe is positioned in the LNG flow below the spill pipe with the tip oriented partly downward so that LNG is continuously drawn into the inner tube through a small orifice. The probe is made of a high thermal conductivity metal. Hot water is flowed through the water jacket and through the flow channel between the three tubes to provide the necessary heat transfer to flash vaporize the LNG passing through the inner channel of the probe. The gasified LNG is transported through a connected hose or tubing extending from the probe to a remote ir sensor which measures the gas composition.

Bianchini, G.M.; McRae, T.G.

1983-06-23T23:59:59.000Z

193

Hydrogen Cars and Water Vapor  

E-Print Network [OSTI]

. This cycle is currently under way with hydrogen fuel cells. As fuel cell cars are suggested as a solutionHydrogen Cars and Water Vapor D.W.KEITHANDA.E.FARRELL'S POLICY FORUM "Rethinking hydrogen cars" (18 misidentified as "zero-emissions vehicles." Fuel cell vehicles emit water vapor. A global fleet could have

Colorado at Boulder, University of

194

UHV-compatible magnetic material for atom optics  

Science Journals Connector (OSTI)

Magnetic videotape is of great interest for trapping and guiding cold atomic vapors, but was hitherto considered unsuitable for manipulating Bose–Einstein condensates (BEC) because of the presumed evolution of...

S.A. Hopkins; E.A. Hinds; M.G. Boshier

2001-07-01T23:59:59.000Z

195

Fuel vapor control device  

SciTech Connect (OSTI)

A fuel vapor control device is described having a valve opening and closing a passage connecting a carburetor and a charcoal canister according to a predetermined temperature. A first coil spring formed by a ''shape memory effect'' alloy is provided to urge the valve to open the passage when the temperature is high. A second coil spring urges the valve to close the passage. A solenoid is provided to urge an armature against the valve to close the passage against the force of the first coil spring when the engine is running. The solenoid heats the first coil spring to generate a spring force therein when the engine is running. When the engine is turned off, the solenoid is deactivated, and the force of the first spring overcomes the force of the second spring to open the passage until such time as the temperature of the first spring drops below the predetermined temperature.

Ota, I.; Nishimura, Y.; Nishio, S.; Yogo, K.

1987-10-20T23:59:59.000Z

196

Laser Ignition  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Ignition Laser Ignition A first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable...

197

Laser cooling by collisional redistribution of radiation  

Science Journals Connector (OSTI)

... in aqueous solutions. Nature 406, 611–614 (2000) Adams, C. S. &Riis, E. Laser cooling and trapping of neutral atoms. Prog. Quantum Electron. 21, ...

Ulrich Vogl; Martin Weitz

2009-09-03T23:59:59.000Z

198

The Dust Settles on Water Vapor Feedback  

Science Journals Connector (OSTI)

...To understand water vapor feedback...shifts in the atmospheric circulation...caused a positive water vapor feedback...temperature. Condensation, evaporation...shifts in the atmospheric circulation...caused a positive water vapor feedback...temperature. Condensation, evaporation...

Anthony D. Del Genio

2002-04-26T23:59:59.000Z

199

Inorganic, Organic, and Total Mercury in Blood and Urine: Cold Vapor Analysis with Automated Flow Injection Sample Delivery  

Science Journals Connector (OSTI)

......and blood and urine specimenswere placed in the dry block heater for 30 min. Di- gestion was considered completewhen foaming...for transfer of nanogram quan- tities of mercury vapor for flameless atomic absorption spec- trophotometry. Anal. Chem. 43......

David E. Nixon; Garry V. Mussmann; Thomas P. Moyer

1996-01-01T23:59:59.000Z

200

Laser isotope purification of lead for use in semiconductor chip interconnects  

SciTech Connect (OSTI)

Lead, used throughout the electronics industries, typically contains small amounts of radioactive {sup 210}Pb (a daughter product of the planet`s ubiquitous {sup 210}U) whose {sup 210}Po daughter emits and {alpha}-particle that is known to cause soft errors in electronic circuits. The {sup 210}Pb is not easily separable by chemical means. This paper describes the generic Atomic Vapor Laser Isotope Separation (AVLIS) process developed at the Lawrence Livermore National Laboratory (LLNL) over the last 20 years, with particular emphasis on recent efforts to develop the process physics and component technologies required to remove the offending {sup 210}Pb using lasers. We have constructed a developmental facility that includes a process laser development area and a test bed for the vaporizer and ion and product collectors. We will be testing much of the equipment and demonstrating pilot-scale AVLIS on a surrogate material later this year. Detection of the very low alpha emission even from commercially available low-alpha lead is challenging. LLNL`s detection capabilities will be described. The goal of the development of lead purification technology is to demonstrate the capability in FY97, and to begin filling orders of up to several MT/y of isotopically purified material in FY98.

Scheibner, K.; Haynam, C.; Worden, E.; Esser, B.

1996-02-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Category:Mercury Vapor | Open Energy Information  

Open Energy Info (EERE)

search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Mercury Vapor page? For detailed information on Mercury Vapor as exploration techniques,...

202

Fabrication of nano-structural arrays by channeling pulsed atomic beams through pulsed-laser standing-waves under off-resonant condition  

E-Print Network [OSTI]

Fabrication of nano-structural arrays by channeling pulsed atomic beams through pulsed 1998 We show that it is feasible to produce one- and two-dimensional nano-structure arrays by passing the reduced dimensions are of the order of nanometers (10 9 m . In particular, nano

Zhu, Xiangdong

203

Novel schemes for the optical manipulation of atoms and molecules.  

E-Print Network [OSTI]

??The range of atoms which can be cooled by lasers is limited to those which have a closed two level structure. Several schemes have been… (more)

Bateman, James

2009-01-01T23:59:59.000Z

204

Optically generated gauge potentials and their effects in cold atoms.  

E-Print Network [OSTI]

??Recent theoretical studies show the possibility of generating optical gauge potentials in neutral atoms using laser beams carrying orbital angular momentum. This is interesting not… (more)

Song, Jianjun

2008-01-01T23:59:59.000Z

205

Electron Diffraction from a Cold Atom Electron Source  

Science Journals Connector (OSTI)

We present single-shot nanosecond and picosecond electron diffraction measurements from gold and graphene using ultracold electrons generated by photoionisation of laser cooled atoms.

Speirs, Rory W; Thompson, Daniel J; Murphy, Dene; Sparkes, Ben M; Scholten, Rob E

206

Vapor etching of nuclear tracks in dielectric materials  

DOE Patents [OSTI]

A process involving vapor etching of nuclear tracks in dielectric materials for creating high aspect ratio (i.e., length much greater than diameter), isolated cylindrical holes in dielectric materials that have been exposed to high-energy atomic particles. The process includes cleaning the surface of the tracked material and exposing the cleaned surface to a vapor of a suitable etchant. Independent control of the temperatures of the vapor and the tracked materials provide the means to vary separately the etch rates for the latent track region and the non-tracked material. As a rule, the tracked regions etch at a greater rate than the non-tracked regions. In addition, the vapor-etched holes can be enlarged and smoothed by subsequent dipping in a liquid etchant. The 20-1000 nm diameter holes resulting from the vapor etching process can be useful as molds for electroplating nanometer-sized filaments, etching gate cavities for deposition of nano-cones, developing high-aspect ratio holes in trackable resists, and as filters for a variety of molecular-sized particles in virtually any liquid or gas by selecting the dielectric material that is compatible with the liquid or gas of interest.

Musket, Ronald G. (Danville, CA); Porter, John D. (Berkeley, CA); Yoshiyama, James M. (Fremont, CA); Contolini, Robert J. (Lake Oswego, OR)

2000-01-01T23:59:59.000Z

207

Demonstration of a vapor density monitoring system using UV radiation generated from quasi-phasematched SHG waveguide devices  

SciTech Connect (OSTI)

Many industrial applications require non-intrusive diagnostics for process monitoring and control. One example is the physical vapor deposition of titanium alloys. In this paper we present a system based on laser absorption spectroscopy for monitoring titanium vapor. Appropriate transitions for monitoring high rate vaporization of titanium require extension of available IR diode technology to the UV. The heart of this vapor density monitoring system is the 390nm radiation generated from quasi-phase matched interactions within periodically poled waveguides. In this paper, key system components of a UV laser absorption spectroscopy based system specific for titanium density monitoring are described. Analysis is presented showing the minimum power levels necessary from the ultraviolet laser source. Performance data for prototype systems using second harmonic generation (SHG) waveguide technology is presented. Application of this technology to other alloy density monitoring systems is discussed.

Galanti, S.A.; Berzins, L.V.; Brown, J.B.; Tamosaitis, R.S.; Bortz, M.L.; Day, T.; Fejer, M.M.; Wang, W.

1996-01-29T23:59:59.000Z

208

Symposium on atomic spectroscopy (SAS-83): abstracts and program  

SciTech Connect (OSTI)

Abstracts of papers given at the symposium are presented. Session topics include: Rydbergs, optical radiators, and planetary atoms; highly ionized atoms; ultraviolet radiation; theory, ion traps, and laser cooling; beam foil; and astronomy. (GHT)

Not Available

1983-09-01T23:59:59.000Z

209

Generation of two-color EPR-entangled optical beams in macroscopic atomic ensembles  

SciTech Connect (OSTI)

We present a protocol for deterministically producing continuous-variable Einstein-Podolsky-Rosen- (EPR-) entangled optical beams in macroscopic atomic ensembles. In contrast to previous cavity-based schemes, our protocol requires only a single pass of two coherent light beams through two spin-polarized free-space atomic vapors, which greatly simplifies the experimental implementation and makes the scheme very efficient. The two entangled modes have a frequency difference of about twice the Zeeman frequency of the atomic vapors, which can be widely tuned via magnetic-field control. Under realistic experimental conditions, we show that large entanglement could be created even with room-temperature atomic vapors.

Wang Mingfeng; Gu Wenjing; Jin Qingli; Zheng Yizhuang [School of Physics and Electronics Information Engineering, Wenzhou University, Wenzhou 325027 (China)

2010-10-15T23:59:59.000Z

210

Chemical vapor deposition of group IIIB metals  

DOE Patents [OSTI]

Coatings of Group IIIB metals and compounds thereof are formed by chemical vapor deposition, in which a heat decomposable organometallic compound of the formula given in the patent where M is a Group IIIB metal, such as lanthanum or yttrium and R is a lower alkyl or alkenyl radical containing from 2 to about 6 carbon atoms, with a heated substrate which is above the decomposition temperature of the organometallic compound. The pure metal is obtained when the compound of the formula 1 is the sole heat decomposable compound present and deposition is carried out under nonoxidizing conditions. Intermetallic compounds such as lanthanum telluride can be deposited from a lanthanum compound of formula 1 and a heat decomposable tellurium compound under nonoxidizing conditions.

Erbil, A.

1989-11-21T23:59:59.000Z

211

Kinetics of wet sodium vapor complex plasma  

SciTech Connect (OSTI)

In this paper, we have investigated the kinetics of wet (partially condensed) Sodium vapor, which comprises of electrons, ions, neutral atoms, and Sodium droplets (i) in thermal equilibrium and (ii) when irradiated by light. The formulation includes the balance of charge over the droplets, number balance of the plasma constituents, and energy balance of the electrons. In order to evaluate the droplet charge, a phenomenon for de-charging of the droplets, viz., evaporation of positive Sodium ions from the surface has been considered in addition to electron emission and electron/ion accretion. The analysis has been utilized to evaluate the steady state parameters of such complex plasmas (i) in thermal equilibrium and (ii) when irradiated; the results have been graphically illustrated. As a significant outcome irradiated, Sodium droplets are seen to acquire large positive potential, with consequent enhancement in the electron density.

Mishra, S. K., E-mail: nishfeb@rediffmail.com [Institute for Plasma Research (IPR), Gandhinagar 382428 (India); Sodha, M. S. [Centre of Energy Studies, Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India)] [Centre of Energy Studies, Indian Institute of Technology Delhi (IITD), New Delhi 110016 (India)

2014-04-15T23:59:59.000Z

212

Nonlinear optics with two trapped atoms  

SciTech Connect (OSTI)

We show theoretically that two atomic dipoles in a resonator constitute a nonlinear medium, whose properties can be controlled through the relative position of the atoms inside the cavity and the detuning and intensity of the driving laser. We identify the parameter regime where the system operates as a parametric amplifier, based on the cascade emission of the collective dipole of the atoms, and determine the corresponding spectrum of squeezing of the field at the cavity output. This dynamics might be observed as a result of self-organization of laser-cooled atoms in resonators.

Fernandez-Vidal, Sonia; Zippilli, Stefano [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); ICFO-Institut de Ciencies Fotoniques, E-08860 Castelldefels, Barcelona (Spain); Morigi, Giovanna [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain)

2007-11-15T23:59:59.000Z

213

Photo-Electric Ionization of Caesium Vapor  

Science Journals Connector (OSTI)

Measurement of photo-electric ionization in gases.—The current from a filament, normally limited by space change, is increased by the presence of positive ions. As shown by Kingdon this effect may be greatly magnified if a small cathode is practically enclosed by the anode so that the ions are imprisoned. This method was used for the detection of photo-electric ionization. Besides possessing extreme sensitivity it is unaffected by photo-electric emission from the electrodes.Photo-electric effect in caesium vapor.—The change in thermionic current with the unresolved radiation from a mercury arc was measured as functions of the applied voltage, filament temperature, and vapor pressure. Then the photo-electric effect as a function of wave-length was studied using a monochromatic illuminator to disperse light from the arc or a Mazda lamp. The ionization per unit flux was found to increase with increasing wave-length to a sharp maximum at the limit 1s=3184A of the principal series, as is required by the Bohr theory. For longer wave-lengths the ionization decreased to about 10 percent at 3400A. Photo-excitation. The simple theory does not admit of ionization by wave-lengths greater than 3184A but the data are in qualitative agreement with the hypothesis that such radiation produces excited atoms which upon collision with other atoms acquire sufficient additional energy to become ionized. Hence, unlike an x-ray limit, the photo-ionization effect for a valence electron is not sharply discontinuous at the true threshold for direct ionization.Photo-ionization photometer and intensitometer. A tube of the type described, with suitable gases for the range of wave-length involved, may be used as a photometer or may be calibrated to measure intensity of radiation directly.

Paul D. Foote and F. L. Mohler

1925-08-01T23:59:59.000Z

214

Vapor deposition of hardened niobium  

DOE Patents [OSTI]

A method of coating ceramic nuclear fuel particles containing a major amount of an actinide ceramic in which the particles are placed in a fluidized bed maintained at ca. 800.degree. to ca. 900.degree. C., and niobium pentachloride vapor and carbon tetrachloride vapor are led into the bed, whereby niobium metal is deposited on the particles and carbon is deposited interstitially within the niobium. Coating apparatus used in the method is also disclosed.

Blocher, Jr., John M. (Columbus, OH); Veigel, Neil D. (Columbus, OH); Landrigan, Richard B. (Columbus, OH)

1983-04-19T23:59:59.000Z

215

Ion-beam-induced epitaxial vapor-phase growth: A molecular-dynamics study  

Science Journals Connector (OSTI)

Low-energy ions which bombard a vapor-deposited film of low adatom mobility during growth mobilize surface atoms in the vicinity of the ion impact, causing a modification in the evolving microstructure. In a two-dimensional molecular-dynamics simulation where inert-gas ions strike a growing film of Lennard-Jones particles, it is demonstrated that ion bombardment during growth causes the filling of voids quenched in during vapor condensation and induces homoepitaxial growth. The dependence of film density and degree of homoepitaxial growth on the ion-to-vapor arrival rate ratio and ion energy is studied in detail.

Karl-Heinz Müller

1987-05-15T23:59:59.000Z

216

Production of higher quality bio-oils by in-line esterification of pyrolysis vapor  

DOE Patents [OSTI]

The disclosure encompasses in-line reactive condensation processes via vapor phase esterification of bio-oil to decease reactive species concentration and water content in the oily phase of a two-phase oil, thereby increasing storage stability and heating value. Esterification of the bio-oil vapor occurs via the vapor phase contact and subsequent reaction of organic acids with ethanol during condensation results in the production of water and esters. The pyrolysis oil product can have an increased ester content and an increased stability when compared to a condensed pyrolysis oil product not treated with an atomized alcohol.

Hilten, Roger Norris; Das, Keshav; Kastner, James R; Bibens, Brian P

2014-12-02T23:59:59.000Z

217

Chemical vapor deposition sciences  

SciTech Connect (OSTI)

Chemical vapor deposition (CVD) is a widely used method for depositing thin films of a variety of materials. Applications of CVD range from the fabrication of microelectronic devices to the deposition of protective coatings. New CVD processes are increasingly complex, with stringent requirements that make it more difficult to commercialize them in a timely fashion. However, a clear understanding of the fundamental science underlying a CVD process, as expressed through computer models, can substantially shorten the time required for reactor and process development. Research scientists at Sandia use a wide range of experimental and theoretical techniques for investigating the science of CVD. Experimental tools include optical probes for gas-phase and surface processes, a range of surface analytic techniques, molecular beam methods for gas/surface kinetics, flow visualization techniques and state-of-the-art crystal growth reactors. The theoretical strategy uses a structured approach to describe the coupled gas-phase and gas-surface chemistry, fluid dynamics, heat and mass transfer of a CVD process. The software used to describe chemical reaction mechanisms is easily adapted to codes that model a variety of reactor geometries. Carefully chosen experiments provide critical information on the chemical species, gas temperatures and flows that are necessary for model development and validation. This brochure provides basic information on Sandia`s capabilities in the physical and chemical sciences of CVD and related materials processing technologies. It contains a brief description of the major scientific and technical capabilities of the CVD staff and facilities, and a brief discussion of the approach that the staff uses to advance the scientific understanding of CVD processes.

NONE

1992-12-31T23:59:59.000Z

218

Laser cooling to quantum degeneracy  

E-Print Network [OSTI]

We report on Bose-Einstein condensation (BEC) in a gas of strontium atoms, using laser cooling as the only cooling mechanism. The condensate is formed within a sample that is continuously Doppler cooled to below 1\\muK on a narrow-linewidth transition. The critical phase-space density for BEC is reached in a central region of the sample, in which atoms are rendered transparent for laser cooling photons. The density in this region is enhanced by an additional dipole trap potential. Thermal equilibrium between the gas in this central region and the surrounding laser cooled part of the cloud is established by elastic collisions. Condensates of up to 10^5 atoms can be repeatedly formed on a timescale of 100ms, with prospects for the generation of a continuous atom laser.

Stellmer, Simon; Grimm, Rudolf; Schreck, Florian

2013-01-01T23:59:59.000Z

219

Laser ablation based fuel ignition  

DOE Patents [OSTI]

There is provided a method of fuel/oxidizer ignition comprising: (a) application of laser light to a material surface which is absorptive to the laser radiation; (b) heating of the material surface with the laser light to produce a high temperature ablation plume which emanates from the heated surface as an intensely hot cloud of vaporized surface material; and (c) contacting the fuel/oxidizer mixture with the hot ablation cloud at or near the surface of the material in order to heat the fuel to a temperature sufficient to initiate fuel ignition.

Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

1998-01-01T23:59:59.000Z

220

Laser ablation based fuel ignition  

DOE Patents [OSTI]

There is provided a method of fuel/oxidizer ignition comprising: (a) application of laser light to a material surface which is absorptive to the laser radiation; (b) heating of the material surface with the laser light to produce a high temperature ablation plume which emanates from the heated surface as an intensely hot cloud of vaporized surface material; and (c) contacting the fuel/oxidizer mixture with the hot ablation cloud at or near the surface of the material in order to heat the fuel to a temperature sufficient to initiate fuel ignition. 3 figs.

Early, J.W.; Lester, C.S.

1998-06-23T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Modeling Nonlinear Magneto-optical Effects in Atomic Vapors  

E-Print Network [OSTI]

to-orientation conversion (AOC), previously discussed insituations rotation due to AOC can have very differentsign of rotation due to AOC is opposite to that predicted by

Rochester, Simon Michael

2010-01-01T23:59:59.000Z

222

Modeling Nonlinear Magneto-optical Effects in Atomic Vapors  

E-Print Network [OSTI]

10.1 Doppler-free transit effect . . . . . . . . . . . .10.2 Doppler-broadened transit effect . . . . . . . . . 10.3Doppler-free transit effect . . . . . . . . . . . . . . . . . . . . . .

Rochester, Simon Michael

2010-01-01T23:59:59.000Z

223

Hadronic Atoms  

E-Print Network [OSTI]

We review the theory of hadronic atoms in QCD+QED. The non-relativistic effective Lagrangian approach, used to describe this type of bound states, is illustrated with the case of pi+pi- atoms. In addition, we discuss the evaluation of isospin-breaking corrections to hadronic atom observables by invoking chiral perturbation theory.

J. Gasser; V. E. Lyubovitskij; A. Rusetsky

2009-03-02T23:59:59.000Z

224

The Vaporization Enthalpies and Vapor Pressures of Some Primary Amines of Pharmaceutical Importance by Correlation Gas  

E-Print Network [OSTI]

by Correlation Gas Chromatography Chase Gobble, Nigam Rath, and James Chickos* Department of Chemistry Information ABSTRACT: Vapor pressures, vaporization, and sublimation enthalpies of several pharmaceuticals and boiling temperatures when available. Sublimation enthalpies and vapor pressures are also evaluated for 1

Chickos, James S.

225

Bringing part of the lab to the field: On-site chromium speciation in seawater by electrodeposition of Cr(III)/Cr(VI) on portable coiled-filament assemblies and measurement in the lab by electrothermal, near-torch vaporization sample introduction and inductively coupled plasma-atomic emission spectrometry  

Science Journals Connector (OSTI)

A field-deployable electrochemical approach to preconcentration, matrix clean up and selective electrodeposition of Cr(III) and Cr(III) + Cr(VI) in seawater is described. Using portable, battery-operated electrochemical instrumentation, Cr species in seawater were electrodeposited in the field on portable coiled-filament assemblies made from Re. Assemblies with dried residues of Cr(III) or Cr(III) + Cr(VI) on them were transported to the lab for concentration determination by electrothermal, near-torch vaporization (NTV) sample introduction and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Electrodeposition offers selective species deposition, preconcentration and matrix clean up from seawater samples. For selective deposition, free Cr(VI) was electrodeposited at ? 0.3 V and Cr(III) + Cr(VI) at ? 1.6 V (both vs Ag/AgCl). Interestingly, at 0 V (vs Ag/AgCl) and in the absence of an electrodeposition potential only Cr(VI) was spontaneously and selectively adsorbed on the coil and reasons for this are given. Due to preconcentration afforded by electrodeposition, the detection limits obtained after a 60 s electrodeposition at the voltages stated above using buffered (pH = 4.7) artificial seawater spiked with either Cr(III) or Cr(VI) were 20 pg/mL for Cr(III) and 10 pg/mL for Cr(VI). For comparison, the detection limit for Cr obtained by pipetting directly on the coil 5 ?L of diluted standard solution was 500 pg/mL, thus it was concluded that electrodeposition offered 40 to 60 fold improvements. Matrix clean up is required due to the high salt content of seawater and this was addressed by simply rinsing the coil with 18.2 M? water without any loss of Cr species. Reasons for this are provided. The method was validated in the lab using buffered artificial seawater and it was used in the field for the first time by sampling seawater, buffering it and immediately electrodepositing Cr species on portable assemblies on-site. Electrodeposition in the field addressed species transformation during sample pre-treatment. Such transformations occur due to sample acidification and may take place during transport and possibly storage prior to analysis. Thus, electrodeposition in the field is more reflective of Cr species concentration at the environmental conditions (e.g., temperature) at the time of sampling. It also opens up the possibility for shipping to the lab portable assemblies with Cr species on them rather than shipping large volumes of sample to the lab, thus also reducing shipping, handling and storage costs.

Hamid R. Badiei; Jennifer McEnaney; Vassili Karanassios

2012-01-01T23:59:59.000Z

226

Compact Quantum Cascade Laser Transmitter  

SciTech Connect (OSTI)

): In this paper we present design considerations, thermal and optical modeling results, and device performance for a ruggedized, compact laser transmitter that utilizes a room temperature quantum cascade (QC) laser source. The QC laser transmitter is intended for portable mid-infrared (3-12 µm) spectroscopy applications, where the atmospheric transmission window is relatively free of water vapor interference and where the molecular rotational vibration absorption features can be used to detect and uniquely identify chemical compounds of interest. Initial QC laser-based sensor development efforts were constrained by the complications of cryogenic operation. However, improvements in both QC laser designs and fabrication processes have provided room-temperature devices that now enable significant miniaturization and integration potential for national security, environmental monitoring, atmospheric science, and industrial safety applications.

Anheier, Norman C.; Hatchell, Brian K.; Gervais, Kevin L.; Wojcik, Michael D.; Krishnaswami, Kannan; Bernacki, Bruce E.

2009-04-01T23:59:59.000Z

227

Atomic, Molecular & Optical Sciences  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atomic, Molecular and Optical Sciences Atomic, Molecular and Optical Sciences The goal of the program is to understand the structure and dynamics of atoms and molecules using photons and ions as probes. The current program is focussed on studying inner-shell photo-ionization and photo-excitation of atoms and molecules, molecular orientation effects in slow collisions, slowing and cooling molecules, and X-ray photo-excitation of laser-dressed atoms. The experimental and theoretical efforts are designed to break new ground and to provide basic knowledge that is central to the programmatic goals of the Department of Energy (DOE). Unique LBNL facilities such as the Advanced Light Source (ALS), the ECR ion sources at the 88-inch cyclotron, and the National Energy Research Scientific Computing Center (NERSC) are

228

VAPORIZATION THERMODYNAMICS OF KCl. COMBINING VAPOR PRESSURE AND GRAVIMETRIC DATA  

E-Print Network [OSTI]

.B. Department of Chemistry, Moscow State University, Moscow, 119899, Russia Bonnell D.W., Hastie J.W. National temperature chemistry situations, vapor pressures are typically less than 100 kPa. The molar volume is p = 101325 Pa). The subscript trs denotes that the changeisfor a transition, typically sublimation

Rudnyi, Evgenii B.

229

Laser Cladding  

Science Journals Connector (OSTI)

Laser cladding is a surface modification process in which a laser beam is used to melt an addition ... process must be clearly differentiated from that of laser surface alloying ( Laser Surface Al...

Prof. Dr. José L. Ocaña; Prof. Janez Grum

2013-01-01T23:59:59.000Z

230

High-resolution laser spectroscopy between 0.9 and 14.3 THz in a supersonic beam: Rydberg-Rydberg transitions of atomic Xe at intermediate n values  

SciTech Connect (OSTI)

A laser-based, pulsed, narrow-band source of submillimeter-wave radiation has been developed that is continuously tunable from 0.1 THz to 14.3 THz. The source is based on difference-frequency mixing in the nonlinear crystal trans-4{sup Prime }-(dimethylamino)-N-methyl-4-stilbazolium tosylate. By varying the pulse length, the bandwidth of the submillimeter-wave radiation can be adjusted between 85 MHz and 2.8 MHz. This new radiation source has been integrated in a vacuum-ultraviolet-submillimeter-ware double-resonance spectrometer, with which low-frequency transitions of atoms and molecules in supersonic beams can be detected mass-selectively by photoionization and time-of-flight mass spectrometry. The properties of the radiation source and spectrometer are demonstrated in a study of 33f Leftwards-Arrow nd Rydberg-Rydberg transitions in Xe with n in the range 16-31. The frequency calibration of the submillimeter-wave radiation was performed with an accuracy of 2.8 MHz. The narrowest lines observed experimentally have a full-width at half-maximum of {approx}3 MHz, which is sufficient to fully resolve the hyperfine structure of the Rydberg-Rydberg transitions of {sup 129}Xe and {sup 131}Xe. A total of 72 transitions were measured in the range between 0.937 THz and 14.245 THz and their frequencies are compared with frequencies calculated by multichannel quantum defect theory.

Haase, Christa; Agner, Josef A.; Merkt, Frederic [Laboratorium fuer Physikalische Chemie, ETH Zuerich, 8093 Zuerich (Switzerland)

2013-06-28T23:59:59.000Z

231

Safeguards Verification Measurements using Laser Ablation, Absorbance Ratio Spectrometry in Gaseous Centrifuge Enrichment Plants  

SciTech Connect (OSTI)

Laser Ablation Absorbance Ratio Spectrometry (LAARS) is a new verification measurement technology under development at the US Department of Energy (DOE) Pacific Northwest National Laboratory (PNNL). LAARS uses three lasers to ablate and then measure the relative isotopic abundance of uranium compounds. An ablation laser is tightly focused on uranium-bearing solids, producing a small atomic uranium vapor plume. Two collinear wavelength-tuned spectrometry lasers transit through the plume and the absorbance of U-235 and U-238 isotopes are measured to determine U-235 enrichment. The measurement is independent of chemical form and degree of dilution with nuisance dust and other materials. LAARS has high relative precision and detection limits approaching the femtogram range for U-235. The sample is scanned and assayed point-by-point at rates reaching 1 million measurements/hour, enabling LAARS to detect and analyze uranium in trace samples. The spectrometer is assembled using primarily commercially available components and features a compact design and automated analysis.Two specific gaseous centrifuge enrichment plant (GCEP) applications of the spectrometer are currently under development: 1) LAARS-Environmental Sampling (ES), which collects and analyzes aerosol particles for GCEP misuse detection and 2) LAARS-Destructive Assay (DA), which enables onsite enrichment DA sample collection and analysis for protracted diversion detection. The two applications propose game-changing technological advances in GCEP safeguards verification.

Anheier, Norman C.; Cannon, Bret D.; Kulkarni, Gourihar R.; Munley, John T.; Nelson, Danny A.; Qiao, Hong (Amy) [Amy; Phillips, Jon R.

2012-07-17T23:59:59.000Z

232

Vacuum vapor deposition gun assembly  

DOE Patents [OSTI]

A vapor deposition gun assembly includes a hollow body having a cylindrical outer surface and an end plate for holding an adjustable heat sink, a hot hollow cathode gun, two magnets for steering the plasma from the gun into a crucible on the heat sink, and a shutter for selectively covering and uncovering the crucible.

Zeren, Joseph D. (Boulder, CO)

1985-01-01T23:59:59.000Z

233

LNG Vaporizer Utilizing Vacuum Steam Condensing  

Science Journals Connector (OSTI)

This report concerns the field test results of a new type of peak-shaving LNG vaporizer (VSV) whose heat source is ... heat of vacuum steam to vaporize and superheat LNG within heat transfer tubes. Prior to the.....

Y. Miyata; M. Hanamure; H. Kujirai; Y. Sato…

1991-01-01T23:59:59.000Z

234

Running-Film Vaporizer for LNG  

Science Journals Connector (OSTI)

Advances in welding technology and steel fabrication techniques have permitted the development of a new concept in cryogenic vaporizers—the running-film plate vaporizer. Although similar in heat transfer philosop...

H. H. West; G. L. Puckett

1975-01-01T23:59:59.000Z

235

Vapor Retarder Classification- Building America Top Innovation  

Broader source: Energy.gov [DOE]

This Building America Innovations profile describes research in vapor retarders. Since 2006 the IRC has permitted Class III vapor retarders like latex paint (see list above) in all climate zones under certain conditions thanks to research by Building America teams.

236

Vapor phase modifiers for oxidative coupling  

DOE Patents [OSTI]

Volatilized metal compounds retard vapor phase alkane conversion reactions in oxidative coupling processes that convert lower alkanes to higher hydrocarbons.

Warren, Barbara K. (Charleston, WV)

1991-01-01T23:59:59.000Z

237

Semiclassical atom  

Science Journals Connector (OSTI)

Semiclassical quantization is incorporated into the average potential approach to atomic physics. The stationary energy functional is shown to be the sum of the Thomas-Fermi functional and a mainly oscillatory part. The latter turns out to be a small correction for sufficiently large atomic numbers, allowing perturbative treatment. Further, a detailed study of semiclassical spectra, with emphasis on energy degeneracy, is performed.

Berthold-Georg Englert and Julian Schwinger

1985-07-01T23:59:59.000Z

238

Evanescent light-matter Interactions in Atomic Cladding Wave Guides  

E-Print Network [OSTI]

Alkali vapors, and in particular rubidium, are being used extensively in several important fields of research such as slow and stored light non-linear optics3 and quantum computation. Additionally, the technology of alkali vapors plays a major role in realizing myriad industrial applications including for example atomic clocks magentometers8 and optical frequency stabilization. Lately, there is a growing effort towards miniaturizing traditional centimeter-size alkali vapor cells. Owing to the significant reduction in device dimensions, light matter interactions are greatly enhanced, enabling new functionalities due to the low power threshold needed for non-linear interactions. Here, taking advantage of the mature Complimentary Metal-Oxide-Semiconductor (CMOS) compatible platform of silicon photonics, we construct an efficient and flexible platform for tailored light vapor interactions on a chip. Specifically, we demonstrate light matter interactions in an atomic cladding wave guide (ACWG), consisting of CMOS ...

Stern, Liron; Goykhman, Ilya; Levy, Uriel

2012-01-01T23:59:59.000Z

239

ccsd00001508, Realization of a magnetically guided atomic beam in the collisional regime  

E-Print Network [OSTI]

to periodically re- plenish with new condensates a gas sample held in an optical dipole trap. The second-Einstein condensation (BEC) [2] and pulsed \\atom lasers" extracted from the condensate [3]. These advances in atom atom laser"). The #12;rst possibility [4] consists in using the \\standard" condensation procedure

240

Vapor Pressures and Heats of Vaporization of Primary Coal Tars  

Office of Scientific and Technical Information (OSTI)

/ PC92544-18 / PC92544-18 VAPOR PRESSURES AND HEATS OF VAPORIZATION OF PRIMARY COAL TARS FINAL REPORT Grant Dates: August, 1992 - November, 1996 Principal Authors: Eric M. Suuberg (PI) and Vahur Oja Report Submitted: April, 1997 Revised: July, 1997 Grant Number: DE-FG22-92PC92544 Report Submitted by: ERIC M. SUUBERG DIVISION OF ENGINEERING BROWN UNIVERSITY PROVIDENCE, RI 02912 TEL. (401) 863-1420 Prepared For: U. S. DEPT. OF ENERGY FEDERAL ENERGY TECHNOLOGY CENTER P.O. BOX 10940 PITTSBURGH, PA 15236 DR. KAMALENDU DAS, FETC, MORGANTOWN , WV TECHNICAL PROJECT OFFICER "US/DOE Patent Clearance is not required prior to the publication of this document" ii United States Government Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Laser Copper Plasma X-ray Source Debris Characterization  

E-Print Network [OSTI]

Laser Copper Plasma X-ray Source Debris Characterization A Thesis Presented by David Hurley 3, 2007 Vice President for Research and Dean of Graduate studies #12;Abstract Laser copper plasma for x-ray lithography. Copper debris in the form of vapor, ions, dust, and high-speed particles

Huston, Dryver R.

242

Vapor deposition of tantalum and tantalum compounds  

SciTech Connect (OSTI)

Tantalum, and many of its compounds, can be deposited as coatings with techniques ranging from pure, thermal chemical vapor deposition to pure physical vapor deposition. This review concentrates on chemical vapor deposition techniques. The paper takes a historical approach. The authors review classical, metal halide-based techniques and current techniques for tantalum chemical vapor deposition. The advantages and limitations of the techniques will be compared. The need for new lower temperature processes and hence new precursor chemicals will be examined and explained. In the last section, they add some speculation as to possible new, low-temperature precursors for tantalum chemical vapor deposition.

Trkula, M. [Los Alamos National Lab., NM (United States). Materials Science and Technology Div.

1996-04-01T23:59:59.000Z

243

Laser Interactions in Nanomaterials Synthesis David B. Geohegan1,2  

E-Print Network [OSTI]

Laser Interactions in Nanomaterials Synthesis David B. Geohegan1,2 , Alex A. Puretzky1,2 , Chris. Laser interactions with materials have unique advantages to explore the rapid synthesis, processing, laser vaporization of solids into background gases provides a wide range of processing conditions

Pennycook, Steve

244

Numerical modeling of short pulse laser interaction with Au nanoparticle surrounded by water  

E-Print Network [OSTI]

for femtosecond laser excitation and time-resolved X-ray probing of gold nanoparticles demonstrates that the vaporNumerical modeling of short pulse laser interaction with Au nanoparticle surrounded by water Alexey, University of Virginia, USA Available online 3 February 2007 Abstract Short pulse laser interaction

Zhigilei, Leonid V.

245

CO2 Laser CVD of Disilane  

Science Journals Connector (OSTI)

Amorphous silicon films were deposited by a CO2 laser CVD (chemical vapor deposition) method using disilane gas. With this gas, the films were deposited reasonably fast at relatively low substrate temperatures of 350°C or above. Unlike monosilane, photo-induced effects in the gas phase following light absorption were negligible in deposition processes, and only the pyrolytic process taking place at the laser-heated substrate was important. Some of the physical properties of deposited films were described.

Takehiko Iwanaga; Mitsugu Hanabusa

1984-01-01T23:59:59.000Z

246

Means and method for vapor generation  

DOE Patents [OSTI]

A liquid, in heat transfer contact with a surface heated to a temperature well above the vaporization temperature of the liquid, will undergo a multiphase (liquid-vapor) transformation from 0% vapor to 100% vapor. During this transition, the temperature driving force or heat flux and the coefficients of heat transfer across the fluid-solid interface, and the vapor percentage influence the type of heating of the fluid--starting as "feedwater" heating where no vapors are present, progressing to "nucleate" heating where vaporization begins and some vapors are present, and concluding with "film" heating where only vapors are present. Unstable heating between nucleate and film heating can occur, accompanied by possibly large and rapid temperature shifts in the structures. This invention provides for injecting into the region of potential unstable heating and proximate the heated surface superheated vapors in sufficient quantities operable to rapidly increase the vapor percentage of the multiphase mixture by perhaps 10-30% and thereby effectively shift the multiphase mixture beyond the unstable heating region and up to the stable film heating region.

Carlson, Larry W. (Oswego, IL)

1984-01-01T23:59:59.000Z

247

Quantum-noise quenching in atomic tweezers  

SciTech Connect (OSTI)

The efficiency of extracting single atoms or molecules from an ultracold bosonic reservoir is theoretically investigated for a protocol based on lasers, coupling the hyperfine state in which the atoms form a condensate to another stable state, in which the atom experiences a tight potential in the regime of collisional blockade, the quantum tweezers. The transfer efficiency into the single-atom ground state of the tight trap is fundamentally limited by the collective modes of the condensate, which are thermally and dynamically excited. The noise due to these excitations can be quenched for sufficiently long laser pulses, thereby achieving high efficiencies. These results show that this protocol can be applied to initializing a quantum register based on tweezer traps for neutral atoms.

Zippilli, Stefano [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Theoretische Physik, Universitaet des Saarlandes, D-66041 Saarbruecken (Germany); Fachbereich Physik and Research Center OPTIMAS, Technische Universitaet Kaiserslautern, D-67663 Kaiserslautern (Germany); Mohring, Bernd; Schleich, Wolfgang [Institut fuer Quantenphysik, Universitaet Ulm, D-89081 Ulm (Germany); Lutz, Eric [Department of Physics, University of Augsburg, D-86135 Augsburg (Germany); Morigi, Giovanna [Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain); Theoretische Physik, Universitaet des Saarlandes, D-66041 Saarbruecken (Germany)

2011-05-15T23:59:59.000Z

248

Quantum-noise quenching in atomic tweezers  

E-Print Network [OSTI]

The efficiency of extracting single atoms or molecules from an ultracold bosonic reservoir is theoretically investigated for a protocol based on lasers, coupling the hyperfine state in which the atoms form a condensate to another stable state, in which the atom experiences a tight potential in the regime of collisional blockade, the quantum tweezers. The transfer efficiency into the single-atom ground state of the tight trap is fundamentally limited by the collective modes of the condensate, which are thermally and dynamically excited. The noise due to these excitations can be quenched for sufficiently long laser pulses, thereby achieving high efficiencies. These results show that this protocol can be applied for initializing a quantum register based on tweezer traps for neutral atoms.

Stefano Zippilli; Bernd Mohring; Eric Lutz; Giovanna Morigi; Wolfgang Schleich

2011-04-15T23:59:59.000Z

249

Hydrogen Production via Chemical Looping Redox Cycles Using Atomic Layer Deposition-Synthesized Iron Oxide and Cobalt Ferrites  

Science Journals Connector (OSTI)

Hydrogen Production via Chemical Looping Redox Cycles Using Atomic Layer Deposition-Synthesized Iron Oxide and Cobalt Ferrites ... Unlike solution and line-of-sight methods used to synthesize metal-substituted ferrites, including solution combustion synthesis,(6) aerial oxidation of aqueous suspensions,(5) sol?gel process,(8) laser molecular beam epitaxy,(21) sputtering,(22) and chemical vapor deposition (CVD),(23) ALD can produce conformal thin films on porous materials. ... The drop in peak H2 production rate is accompanied by a ?55% decrease in the total amount of H2 produced (see Table 1) and a similar decrease in the time required to achieve 95% conversion, suggesting a loss of accessible iron in this material. ...

Jonathan R. Scheffe; Mark D. Allendorf; Eric N. Coker; Benjamin W. Jacobs; Anthony H. McDaniel; Alan W. Weimer

2011-03-24T23:59:59.000Z

250

Inelastic Scattering of 20-kev Electrons in Metal Vapors  

Science Journals Connector (OSTI)

The low-energy losses of 20-kev electrons passing through the vapors of Zn, Cd, Hg, Na, K, Mg, Ca, Sb, Pb, and KCl, have been measured by using an electrostatic analyzer previously used for measuring electron energy losses in thin metal films. The atomic transitions corresponding to the measured energy losses are in many cases fairly easily established. However, there remain some which are questionable due to the fact that there is more than one feasible transition with energy differences of the order of the given energy loss. It is established that the principal interaction results in the excitation from the ground state of the neutral atom to the first excited level—the resonance excitation. It is also found that dipole excitations predominate

Lewis B. Leder

1957-09-15T23:59:59.000Z

251

Laser Ignition  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Ignition Laser Ignition Laser Ignition A first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Available for thumbnail of Feynman Center (505) 665-9090 Email Laser Ignition A first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In two embodiments the beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion

252

E-Print Network 3.0 - atomic size effect Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Biochemistry, Yale University Collection: Biology and Medicine ; Biotechnology 38 Laser cooling and trapping of atoms H.J. Metcalf and P. van der Straten Summary: are of size...

253

E-Print Network 3.0 - atomic fluorescence spectrometry Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

avril1994 Summary: down to about 310 nm. Such powers are sufficient for laser atomic absorption spectrometry (LAAS... spectrometry where the low-frequency noise of the...

254

E-Print Network 3.0 - absorber-materials atomic numbers Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

. With two laser sources, however, quantum interference can be used to ensure that atomic absorption... is eliminated, while retaining a large nonlinear response. A downside...

255

E-Print Network 3.0 - atoms two-photon above-threshold Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

created, which can be considered above threshold ionization ATI . Unlike in the seminal atomic ATI studies... absorption of four laser photons, equivalent to 20 eV excitation...

256

E-Print Network 3.0 - atom beam activation Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

emits coherent electromagnetic waves. Coherence means, for instance, that atom laser beams... emission of photons, a light amplification process. Similarly, an ... Source:...

257

E-Print Network 3.0 - atom optical lattices Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

An optical lattice with single lattice Summary: lattice spacing of a CO2 laser optical lattice to resolve and control atoms in single lattice sites... on...

258

Atom Interferometry  

ScienceCinema (OSTI)

Atom de Broglie wave interferometry has emerged as a tool capable of addressing a diverse set of questions in gravitational and condensed matter physics, and as an enabling technology for advanced sensors in geodesy and navigation. This talk will review basic principles, then discuss recent applications and future directions. Scientific applications to be discussed include measurement of G (Newton?s constant), tests of the Equivalence Principle and post-Newtonian gravity, and study of the Kosterlitz-Thouless phase transition in layered superfluids. Technology applications include development of precision gryoscopes and gravity gradiometers. The talk will conclude with speculative remarks looking to the future: Can atom interference methods be sued to detect gravity waves? Can non-classical (entangled/squeezed state) atom sources lead to meaningful sensor performance improvements?

Mark Kasevich

2010-01-08T23:59:59.000Z

259

E-Print Network 3.0 - atomic energy levels Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the number of atoms in the level m of the cavity, and n the number of photons... Atom Laser (For McGraw-Hill 1999 Yearbook of Science & Technology, companion volume to...

260

E-Print Network 3.0 - atomic research center Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

the (111) direction. Atoms in the optical molasses glow brightly at the center... Laser cooling and trapping of atoms H.J. Metcalf and P. van der Straten ... Source: van der...

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

E-Print Network 3.0 - atomic contacts effect Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

zero net 12;5 effect on the atomic momentum. Thus the force from ab- sorption... Laser cooling and trapping of atoms H.J. Metcalf and P. van der Straten ... Source: van der...

262

E-Print Network 3.0 - atomic beam produced Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

in the scattering of light by a condensate Summary: for the generation of directed beams of atoms and light. B C D E F G Laser Beam Light Atoms A Observation... ). However,...

263

Method of physical vapor deposition of metal oxides on semiconductors  

DOE Patents [OSTI]

A process for growing a metal oxide thin film upon a semiconductor surface with a physical vapor deposition technique in a high-vacuum environment and a structure formed with the process involves the steps of heating the semiconductor surface and introducing hydrogen gas into the high-vacuum environment to develop conditions at the semiconductor surface which are favorable for growing the desired metal oxide upon the semiconductor surface yet is unfavorable for the formation of any native oxides upon the semiconductor. More specifically, the temperature of the semiconductor surface and the ratio of hydrogen partial pressure to water pressure within the vacuum environment are high enough to render the formation of native oxides on the semiconductor surface thermodynamically unstable yet are not so high that the formation of the desired metal oxide on the semiconductor surface is thermodynamically unstable. Having established these conditions, constituent atoms of the metal oxide to be deposited upon the semiconductor surface are directed toward the surface of the semiconductor by a physical vapor deposition technique so that the atoms come to rest upon the semiconductor surface as a thin film of metal oxide with no native oxide at the semiconductor surface/thin film interface. An example of a structure formed by this method includes an epitaxial thin film of (001)-oriented CeO.sub.2 overlying a substrate of (001) Ge.

Norton, David P. (Knoxville, TN)

2001-01-01T23:59:59.000Z

264

Non-Vapor Compression HVAC Technologies Report  

Broader source: Energy.gov [DOE]

While vapor-compression technologies have served heating, ventilation, and air-conditioning (HVAC) needs very effectively, and have been the dominant HVAC technology for close to 100 years, the conventional refrigerants used in vapor-compression equipment contribute to global climate change when released to the atmosphere. The Building Technologies Office is evaluating low-global warming potential (GWP) alternatives to vapor-compression technologies.

265

Mercury Vapor (Kooten, 1987) | Open Energy Information  

Open Energy Info (EERE)

Mercury Vapor (Kooten, 1987) Mercury Vapor (Kooten, 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor (Kooten, 1987) Exploration Activity Details Location Unspecified Exploration Technique Mercury Vapor Activity Date Usefulness useful DOE-funding Unknown Notes Surface soil-mercury surveys are an inexpensive and useful exploration tool for geothermal resources. ---- Surface geochemical surveys for mercury were conducted in 16 areas in 1979-1981 by ARCO Oil and Gas Company as part of its geothermal evaluation program. Three techniques used together have proved satisfactory in evaluating surface mercury data. These are contouring, histograms and cumulative frequency plots of the data. Contouring geochemical data and constructing histograms are standard

266

Vapor phase modifiers for oxidative coupling  

DOE Patents [OSTI]

Volatilized metal compounds are described which are capable of retarding vapor phase alkane conversion reactions in oxidative coupling processes that convert lower alkanes to higher hydrocarbons.

Warren, B.K.

1991-12-17T23:59:59.000Z

267

Capabilities of Laser Ablation Mass Spectrometry in the Differentiation of Natural and Artificial Opal Gemstones  

Science Journals Connector (OSTI)

Si+,?K+,?Ca+, Zr+,?Hf+ ... The interaction of a laser beam with an inorganic compound leads different processes such as surface heating, phase change (fusion and vaporization of the target), ablation, and ionization20,21 to occur. ...

Eric Erel; Frédéric Aubriet; Gisèle Finqueneisel; Jean-François Muller

2003-10-22T23:59:59.000Z

268

CO2 laser CVD of a-Si:H: in situ gas analysis and model calculations  

Science Journals Connector (OSTI)

and disilane Si2H6 induced by continuous wave CO2 laser irradiation has been investigated under the conditions of chemical vapor deposition (CVD) of amorphous hydrogenated silicon a-Si:H. At the very position of...

F. Falk; G. Mollekopf; H. Stafast

1998-11-01T23:59:59.000Z

269

Fine structure changing collisions between ultra-cold lithium atoms  

SciTech Connect (OSTI)

The authors have designed and assembled an experiment to determine the rate of fine structure changing collisions between ultra-cold ({approximately} 1 mK) laser cooled Li atoms. The atoms are confined by a magneto-optical trap which consists of six polarized orthogonal laser beams tuned slightly below the 2S{sub 1/2}-2P{sub 3/2} resonance frequency of lithium. Measurements show that about 2 x 10{sup 7} atoms are confined to a roughly spherical region of about 1 mm in diameter. Fine structure changing collisions occur when an atom in the 2S{sub 1/2} state and an atom in the 2P{sub 3/2} state collide, and yield an atom in the 2S{sub 1/2} state and an atom in the 2P{sub 1/2} state, with an energy release corresponding to about 10 GHz. This energy adds kinetic energy to the atoms in the trap, and knocks atoms out of the trap. The authors have devised a method to measure the rate of this collisional loss mechanism. The method uses a laser diode and a dye laser to selectively photo-ionize the 2P{sub 1/2} atoms, and a channeltron particle multipiler measures the rate of ion formation. We will report the progress of this experiment.

Anderson, B.P.; Ritchie, N.W.M.; Xiao, Y.Y. [and others

1992-12-01T23:59:59.000Z

270

Near real time vapor detection and enhancement using aerosol adsorption  

SciTech Connect (OSTI)

A vapor sample detection method where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample.

Novick, Vincent J.; Johnson, Stanley A.

1997-12-01T23:59:59.000Z

271

Near real time vapor detection and enhancement using aerosol adsorption  

DOE Patents [OSTI]

A vapor sample detection method is described where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample. 13 figs.

Novick, V.J.; Johnson, S.A.

1999-08-03T23:59:59.000Z

272

Near real time vapor detection and enhancement using aerosol adsorption  

DOE Patents [OSTI]

A vapor sample detection method where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample.

Novick, Vincent J. (Downers Grove, IL); Johnson, Stanley A. (Countryside, IL)

1999-01-01T23:59:59.000Z

273

Spectroscopic Observation of Resonant Electric Dipole-Dipole Interactions between Cold Rydberg Atoms  

E-Print Network [OSTI]

Atoms K. Afrousheh, P. Bohlouli-Zanjani, D. Vagale, A. Mugford, M. Fedorov, and J. D. D. Martin between cold Rydberg atoms were observed using microwave spectroscopy. Laser-cooled 85Rb atoms pulse transferred a fraction of these Rydberg atoms to the 46p3=2 state. A second microwave pulse

Le Roy, Robert J.

274

Synthesis of carbon nanotubes on diamond-like carbon by the hot filament plasma-enhanced chemical vapor deposition method  

E-Print Network [OSTI]

by laser ablation of carbon rods, direct current arc-discharge between electrodes, or by chemical vapor emission scanning electron microscopy (FE-SEM), high resolution transmission scanning electron micro- scopy natural oxide. The synthesis of the DLC films was carried out using 13.56 MHz RF-PECVD. Prior to the DLC

Hong, Byungyou

275

G-Band Vapor Radiometer Precipitable Water Vapor (GVRPWV) Value-Added Product  

SciTech Connect (OSTI)

The G-Band Vapor Radiometer Precipitable Water Vapor (GVRPWV) value-added product (VAP) computes precipitable water vapor using neural network techniques from data measured by the GVR. The GVR reports time-series measurements of brightness temperatures for four channels located at 183.3 ± 1, 3, 7, and 14 GHz.

Koontz, A; Cadeddu, M

2012-12-05T23:59:59.000Z

276

Colloquium: Artificial gauge potentials for neutral atoms  

SciTech Connect (OSTI)

When a neutral atom moves in a properly designed laser field, its center-of-mass motion may mimic the dynamics of a charged particle in a magnetic field, with the emergence of a Lorentz-like force. In this Colloquium the physical principles at the basis of this artificial (synthetic) magnetism are presented. The corresponding Aharonov-Bohm phase is related to the Berry's phase that emerges when the atom adiabatically follows one of the dressed states of the atom-laser interaction. Some manifestations of artificial magnetism for a cold quantum gas, in particular, in terms of vortex nucleation are discussed. The analysis is then generalized to the simulation of non-Abelian gauge potentials and some striking consequences are presented, such as the emergence of an effective spin-orbit coupling. Both the cases of bulk gases and discrete systems, where atoms are trapped in an optical lattice, are addressed.

Dalibard, Jean; Gerbier, Fabrice; Juzeliunas, Gediminas; Oehberg, Patrik [Laboratoire Kastler Brossel, CNRS, UPMC, Ecole normale superieure, 24 rue Lhomond, 75005, Paris (France); Institute of Theoretical Physics and Astronomy, Vilnius University, A. Gostauto 12, Vilnius 01108 (Lithuania); SUPA, Department of Physics, Heriot-Watt University, Edinburgh, EH14 4AS (United Kingdom)

2011-10-01T23:59:59.000Z

277

ccsd-00001508,version1-1May2004 Realization of a magnetically guided atomic beam in the collisional regime  

E-Print Network [OSTI]

to periodically re- plenish with new condensates a gas sample held in an optical dipole trap. The second-Einstein condensation (BEC) [2] and pulsed "atom lasers" extracted from the condensate [3]. These advances in atom atom laser"). The first possibility [4] consists in using the "standard" condensation procedure

Boyer, Edmond

278

Integrated rig for the production of boron nitride nanotubes via the pressurized vapor-condenser method  

DOE Patents [OSTI]

An integrated production apparatus for production of boron nitride nanotubes via the pressure vapor-condenser method. The apparatus comprises: a pressurized reaction chamber containing a continuously fed boron containing target having a boron target tip, a source of pressurized nitrogen and a moving belt condenser apparatus; a hutch chamber proximate the pressurized reaction chamber containing a target feed system and a laser beam and optics.

Smith, Michael W; Jordan, Kevin C

2014-03-25T23:59:59.000Z

279

Chapter 7 - Nanofabrication via atom optics  

Science Journals Connector (OSTI)

Publisher Summary This chapter presents a review of the basic concepts that are used for atomoptical nanofabrication, as well as a discussion of the progress to date in realizations of the techniques. As a new approach to nanofabrication, atom optics offers the possibility of several advantages over existing techniques. For one thing, the fundamental diffraction limit imposed on resolution, present in any process where one attempts to focus particles (whether photons, charged particles, or neutral atoms), can be very small for atoms. Furthermore, atom optics can be used both in a direct deposition mode, where neutral atoms are focused by atom lenses into an extremely fine spot as they deposit onto a substrate, and also in a lithography mode, where focused atoms are used to expose a suitable resist material. In the direct deposition mode, nanostructures can be fabricated in a clean, resist-free environment, with little or no damage to the underlying substrate. Thus, the process can be very localized, with very little scattering and resist penetration. In either mode, parallelism, which is advantageous when issues of fabrication speed and/or long-range spatial coherence are important, can be achieved with very high dimensional accuracy over a large area of the substrate using laser focusing of atoms in a laser interference pattern.

Jabez J. McClelland

2000-01-01T23:59:59.000Z

280

Laser-assisted nuclear photoeffect  

E-Print Network [OSTI]

Proton emission from nuclei via the nuclear photoeffect in the combined electromagnetic fields of a gamma-ray photon and an intense laser wave is studied. An S-matrix approach to the process is developed by utilizing methods known from the theory of nonperturbative laser-atom interactions. As a specific example, photo-proton ejection from halo nuclei is considered. We show that, due to the presence of the laser field, rich sideband structures arise in the photo-proton energy spectra. Their dependence on the parameters and relative orientation of the photon fields is discussed.

Anis Dadi; Carsten Müller

2012-04-17T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Quantitative organic vapor-particle sampler  

DOE Patents [OSTI]

A quantitative organic vapor-particle sampler for sampling semi-volatile organic gases and particulate components. A semi-volatile organic reversible gas sorbent macroreticular resin agglomerates of randomly packed microspheres with the continuous porous structure of particles ranging in size between 0.05-10 .mu.m for use in an integrated diffusion vapor-particle sampler.

Gundel, Lara (Berkeley, CA); Daisey, Joan M. (Walnut Creek, CA); Stevens, Robert K. (Cary, NC)

1998-01-01T23:59:59.000Z

282

LNG fire and vapor control system technologies  

SciTech Connect (OSTI)

This report provides a review of fire and vapor control practices used in the liquefied natural gas (LNG) industry. Specific objectives of this effort were to summarize the state-of-the-art of LNG fire and vapor control; define representative LNG facilities and their associated fire and vapor control systems; and develop an approach for a quantitative effectiveness evaluation of LNG fire and vapor control systems. In this report a brief summary of LNG physical properties is given. This is followed by a discussion of basic fire and vapor control design philosophy and detailed reviews of fire and vapor control practices. The operating characteristics and typical applications and application limitations of leak detectors, fire detectors, dikes, coatings, closed circuit television, communication systems, dry chemicals, water, high expansion foam, carbon dioxide and halogenated hydrocarbons are described. Summary descriptions of a representative LNG peakshaving facility and import terminal are included in this report together with typical fire and vapor control systems and their locations in these types of facilities. This state-of-the-art review identifies large differences in the application of fire and vapor control systems throughout the LNG industry.

Konzek, G.J.; Yasutake, K.M.; Franklin, A.L.

1982-06-01T23:59:59.000Z

283

Resonance Ionization Laser Ion Sources  

E-Print Network [OSTI]

The application of the technique of laser resonance ionization to the production of singly charged ions at radioactive ion beam facilities is discussed. The ability to combine high efficiency and element selectivity makes a resonance ionization laser ion source (RILIS) an important component of many radioactive ion beam facilities. At CERN, for example, the RILIS is the most commonly used ion source of the ISOLDE facility, with a yearly operating time of up to 3000 hours. For some isotopes the RILIS can also be used as a fast and sensitive laser spectroscopy tool, provided that the spectral resolution is sufficiently high to reveal the influence of nuclear structure on the atomic spectra. This enables the study of nuclear properties of isotopes with production rates even lower than one ion per second and, in some cases, enables isomer selective ionization. The solutions available for the implementation of resonance laser ionization at radioactive ion beam facilities are summarized. Aspects such as the laser r...

Marsh, B

2013-01-01T23:59:59.000Z

284

ARM - Field Campaign - Water Vapor IOP  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

govCampaignsWater Vapor IOP govCampaignsWater Vapor IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Water Vapor IOP 2000.09.18 - 2000.10.08 Lead Scientist : Henry Revercomb Data Availability Yes For data sets, see below. Description Scientific hypothesis: 1. Microwave radiometer (MWR) observations of the 22 GHz water vapor line can accurately constrain the total column amount of water vapor (assuming a calibration accuracy of 0.5 degC or better, which translates into 0.35 mm PWV). 2. Continuous profiling by Raman lidar provides a stable reference for handling sampling problems and observes a fixed column directly above the site only requiring a single height- independent calibration factor. 3. Agreement between the salt-bath calibrated in-situ probes, chilled

285

Atom Probe Tomography | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atom Probe Tomography Atom Probe Tomography The LEAP 4000 XHR local electrode atom probe tomography instrument enabled the first-ever comprehensive and accurate 3-D chemical...

286

An enriched 40 K source for fermionic atom studies  

E-Print Network [OSTI]

to the vacuum pumps or due to adsorption of the alkali atoms onto metal surfaces in the chamber may be controlled to some extent with temperature. Heating the source will increase the vapor pressure above that occurs inside the vacuum chamber. The metal is released, or evaporated, simply by Ohmic heating

Jin, Deborah

287

Laser ignition  

DOE Patents [OSTI]

In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. The beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being recombined with the first portion after a delay before injection into the ignitor laser. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones.

Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

2002-01-01T23:59:59.000Z

288

Ground Gravity Survey At Cove Fort Area - Vapor (Warpinski, Et...  

Open Energy Info (EERE)

Vapor (Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Ground Gravity Survey At Cove Fort Area - Vapor (Warpinski, Et...

289

Hydrogen-Bond Acidic Polymers for Chemical Vapor Sensing. | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Acidic Polymers for Chemical Vapor Sensing. Hydrogen-Bond Acidic Polymers for Chemical Vapor Sensing. Abstract: A review with 171 references. Hydrogen-bond acidic polymers for...

290

Page 1Laser Safety Training Laser Institute of America Laser Safety Laser Institute of America  

E-Print Network [OSTI]

Page 1Laser Safety Training © Laser Institute of America 1 Laser Safety © Laser Institute of America Laser Safety: Hazards, Bioeffects, and Control Measures Laser Institute of America Gus Anibarro Education Manager 2Laser Safety © Laser Institute of America Laser Safety Overview Laser Safety Accidents

Farritor, Shane

291

Laser Telecommunication timeLaser beam  

E-Print Network [OSTI]

Laser Telecommunication Experiment Laser time Laser beam intensity timeLaser beam Laser battery Laser connected to a circuit without a modulator. Bottom graph illustrates what happen when a modulating signal is superimposed to the DC voltage driving the laser Laser beam intensity DC Input voltage DC

La Rosa, Andres H.

292

Vaporization property and crystal structure of lithium metatitanate with excess Li  

Science Journals Connector (OSTI)

Abstract The vaporization property and the crystal structure of lithium metatitanate with excess Li, which has been developed as an advanced tritium breeder, were studied. After synthesizing the lithium metatitanate specimens with Li/Ti = 2.0–2.3 (at mixing of the starting materials), the vaporization properties were investigated by measuring the mass losses during heating at 1173 K. The Li excessive specimens indicated higher rates of mass loss than the stoichiometric one during heating as long as excessive lithium atom exists. The crystal structures of stoichiometric and nonstoichiometric lithium metatitanates were discussed with the result of neutron diffraction and the refined structural parameters by Rietveld analysis. The refinement (Rwp = 7.98, Rp = 5.96 and Re = 2.58) suggested that lithium metatitanate with excess Li has ?-Li2TiO3 structure and excess Li atoms exist at unstable sites with the formation of reduced titanium or site vacancies.

Keisuke Mukai; Kazuya Sasaki; Takayuki Terai; Akihiro Suzuki; Tsuyoshi Hoshino

2013-01-01T23:59:59.000Z

293

Vapor-Particle Separation Using Microporous Metallic Membrane in Crossflow Filtration  

SciTech Connect (OSTI)

Simultaneous separation of vapor and particles in industrial processes could be a key step toward manufacturing of high-quality goods. The separation is critical for successful measurement of volatile or semi-volatile aerosol particles, which no reliable technique exists. We have developed a technique for separation of vapor and particles simultaneously using a specialty microporous metallic membrane. The separator allows the thermally denuded particles traverse straight through the membrane tube, while the vapor molecules permeate through the membrane, separate from the particles and are removed subsequently. The separation technique virtually eliminates the possibility of contamination by vapor re- condensation. We tested the prototype of the vapor-particle separator (VPS) using aerosols prepared from sodium chloride to represent non-volatile aerosols. Chemical like dioctyl phthalate was chosen to represent volatile particles. The test aerosol particles were generated by an atomizer followed by a tandem differential mobility analyser to produce a stream of monodisperse particles in the size range of 10 to 100 nm. In real world particles, we tested the VPS using diesel engine particles that is a mixture of complex chemical composition. Number concentration of the nonvolatile particles reduced as the temperature increased, but the mode diameter of the aerosol population remained unchanged. Number concentration of the volatile particles was also reduced as the temperature increased, but their mode diameters became smaller as particles shrunk in diameter. Differences in the thermal behaviour of the particles were attributed to its transition energy barrier and evaporation rate. Mass balance analysis suggests the separation of vapor and test particles was reasonably complete. Thus, we conclude the VPS could provide an effective means for quantitative characterization of aerosol volatility and separation of vapors from particles.

Cheng, Mengdawn [ORNL] [ORNL

2013-01-01T23:59:59.000Z

294

Trapping of ultracold atoms in a hollow-core photonic crystal fiber Caleb A. Christensen,1  

E-Print Network [OSTI]

light in multiple modes in the cladding or core. Such fibers are susceptible to speckle or inhomogeneous have succeeded in trapping ultracold atoms 13 or guiding thermal 14 or laser-cooled atoms 15 through laser cooling and rf evaporation in a dc Ioffe-Pritchard magnetic trap, then load the BEC into a red

295

Laser microphone  

DOE Patents [OSTI]

A microphone for detecting sound pressure waves includes a laser resonator having a laser gain material aligned coaxially between a pair of first and second mirrors for producing a laser beam. A reference cell is disposed between the laser material and one of the mirrors for transmitting a reference portion of the laser beam between the mirrors. A sensing cell is disposed between the laser material and one of the mirrors, and is laterally displaced from the reference cell for transmitting a signal portion of the laser beam, with the sensing cell being open for receiving the sound waves. A photodetector is disposed in optical communication with the first mirror for receiving the laser beam, and produces an acoustic signal therefrom for the sound waves.

Veligdan, James T. (Manorville, NY)

2000-11-14T23:59:59.000Z

296

Efficient Collection of 221Fr into a Vapor Cell Magneto-optical Trap  

Science Journals Connector (OSTI)

We have efficiently loaded a vapor cell magneto-optical trap from an orthotropic source of 221Fr with a trapping efficiency of 56(10)%. A novel detection scheme allowed us to measure 900 trapped atoms with a signal to noise ratio of ?60 in 1 sec. We have measured the energies and the hyperfine constants of the 7P1/22 and 7P3/22 states.

Z.-T. Lu; K. L. Corwin; K. R. Vogel; C. E. Wieman; T. P. Dinneen; J. Maddi; Harvey Gould

1997-08-11T23:59:59.000Z

297

Recovering hydrocarbons from hydrocarbon-containing vapors  

DOE Patents [OSTI]

Values are recovered from a hydrocarbon-containing vapor by contacting the vapor with quench liquid consisting essentially of hydrocarbons to form a condensate and a vapor residue, the condensate and quench fluid forming a combined liquid stream. The combined liquid stream is mixed with a viscosity-lowering liquid to form a mixed liquid having a viscosity lower than the viscosity of the combined liquid stream to permit easy handling of the combined liquid stream. The quench liquid is a cooled portion of the mixed liquid. Viscosity-lowering liquid is separated from a portion of the mixed liquid and cycled to form additional mixed liquid.

Mirza, Zia I. (La Verne, CA); Knell, Everett W. (Los Alamitos, CA); Winter, Bruce L. (Danville, CA)

1980-09-30T23:59:59.000Z

298

Laser Locking with Doppler-free Saturated Absorption Spectroscopy  

E-Print Network [OSTI]

there are many ways to stabilize the frequency of a laser, atomic absorption lines are particularly accurate are made, it becomes possible to resolve the saturated absorption lines that correspond to specific atomic absorption spectroscopy. This affects the number of atoms in the ground state and excited state

Novikova, Irina

299

Two-color Laser Desorption of Nanostructured MgO Thin Films....  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Two-color Laser Desorption of Nanostructured MgO Thin Films. Two-color Laser Desorption of Nanostructured MgO Thin Films. Abstract: Neutral magnesium atom emission from...

300

Harmonic wavelet analysis of modulated tunable diode laser absorption spectroscopy signals  

E-Print Network [OSTI]

of the direct absorption characteristics of atomic or molecular absorption lines. This is accomplishedHarmonic wavelet analysis of modulated tunable diode laser absorption spectroscopy signals Hong analyses of tunable diode laser absorption spectroscopy signals were performed. The absorption spectroscopy

Cheng, Harry H.

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Quantum computing with atomic Josephson junction arrays  

SciTech Connect (OSTI)

We present a quantum computing scheme with atomic Josephson junction arrays. The system consists of a small number of atoms with three internal states and trapped in a far-off-resonant optical lattice. Raman lasers provide the 'Josephson' tunneling, and the collision interaction between atoms represent the 'capacitive' couplings between the modes. The qubit states are collective states of the atoms with opposite persistent currents. This system is closely analogous to the superconducting flux qubit. Single-qubit quantum logic gates are performed by modulating the Raman couplings, while two-qubit gates result from a tunnel coupling between neighboring wells. Readout is achieved by tuning the Raman coupling adiabatically between the Josephson regime to the Rabi regime, followed by a detection of atoms in internal electronic states. Decoherence mechanisms are studied in detail promising a high ratio between the decoherence time and the gate operation time.

Tian Lin; Zoller, P. [Institute for Theoretical Physics, University of Innsbruck, A-6020 Innsbruck (Austria)

2003-10-01T23:59:59.000Z

302

Quantum Computing with Atomic Josephson Junction Arrays  

E-Print Network [OSTI]

We present a quantum computing scheme with atomic Josephson junction arrays. The system consists of a small number of atoms with three internal states and trapped in a far-off resonant optical lattice. Raman lasers provide the "Josephson" tunneling, and the collision interaction between atoms represent the "capacitive" couplings between the modes. The qubit states are collective states of the atoms with opposite persistent currents. This system is closely analogous to the superconducting flux qubit. Single qubit quantum logic gates are performed by modulating the Raman couplings, while two-qubit gates result from a tunnel coupling between neighboring wells. Readout is achieved by tuning the Raman coupling adiabatically between the Josephson regime to the Rabi regime, followed by a detection of atoms in internal electronic states. Decoherence mechanisms are studied in detail promising a high ratio between the decoherence time and the gate operation time.

Lin Tian; P. Zoller

2003-06-12T23:59:59.000Z

303

Dynamic high-speed spatial manipulation of cold atoms using acousto-optic and spatial light modulation  

Science Journals Connector (OSTI)

We demonstrate an experimental technique for high-resolution, high-speed spatial manipulation of atom clouds. By combining holographically engineered laser beams from a spatial light...

Fatemi, F K; Bashkansky, M; Dutton, Z

2007-01-01T23:59:59.000Z

304

Strain relaxation in graphene grown by chemical vapor deposition  

SciTech Connect (OSTI)

The growth of single layer graphene by chemical vapor deposition on polycrystalline Cu substrates induces large internal biaxial compressive strain due to thermal expansion mismatch. Raman backscattering spectroscopy and atomic force microscopy were used to study the strain relaxation during and after the transfer process from Cu foil to SiO{sub 2}. Interestingly, the growth of graphene results in a pronounced ripple structure on the Cu substrate that is indicative of strain relaxation of about 0.76% during the cooling from the growth temperature. Removing graphene from the Cu substrates and transferring it to SiO{sub 2} results in a shift of the 2D phonon line by 27?cm{sup ?1} to lower frequencies. This translates into additional strain relaxation. The influence of the processing steps, used etching solution and solvents on strain, is investigated.

Troppenz, Gerald V., E-mail: gerald.troppenz@helmholtz-berlin.de; Gluba, Marc A.; Kraft, Marco; Rappich, Jörg; Nickel, Norbert H. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Institut für Silizium Photovoltaik, Kekuléstr. 5, D-12489 Berlin (Germany)

2013-12-07T23:59:59.000Z

305

1.471.49-m InGaAsPInP diode laser arrays A. Gourevitch,a)  

E-Print Network [OSTI]

and analytically investigated. The InGaAsP/InP heterostructures were grown by orga- nometallic chemical vapor. Direct resonant pumping of erbium lasers performed in absorption bands near 1.47 and 1.54 m eliminates

306

CO Laser Absorption Coefficients for Gases of Biological Relevance: H2O, CO2, Ethanol, Acetaldehyde, and Ethylene  

Science Journals Connector (OSTI)

The pressure-broadened spectra of water vapor, carbon dioxide, ethylene, ethanol, and acetaldehyde were recorded with the use of a liquid nitrogen-cooled CO laser-based photoacoustic...

Persijn, S T; Veltman, R H; Oomens, J; Harren, F J M; Parker, D H

2000-01-01T23:59:59.000Z

307

Standard Model tests with trapped radioactive atoms  

E-Print Network [OSTI]

We review the use of laser cooling and trapping for Standard Model tests, focusing on trapping of radioactive isotopes. Experiments with neutral atoms trapped with modern laser cooling techniques are testing several basic predictions of electroweak unification. For nuclear $\\beta$ decay, demonstrated trap techniques include neutrino momentum measurements from beta-recoil coincidences, along with methods to produce highly polarized samples. These techniques have set the best general constraints on non-Standard Model scalar interactions in the first generation of particles. They also have the promise to test whether parity symmetry is maximally violated, to search for tensor interactions, and to search for new sources of time reversal violation. There are also possibilites for exotic particle searches. Measurements of the strength of the weak neutral current can be assisted by precision atomic experiments using traps of small numbers of radioactive atoms, and sensitivity to possible time-reversal violating electric dipole moments can be improved.

J. A. Behr; G. Gwinner

2009-03-04T23:59:59.000Z

308

Laser theory in manifest Lindblad form  

E-Print Network [OSTI]

We discuss the laser theory for a single-mode laser with nonlinear gain. We focus in particular on a micromaser which is pumped with a dilute beam of excited atoms crossing the laser cavity. In the weak-coupling regime, an expansion in the coupling strength is developed that preserves the Lindblad form of the master equation, securing the positivity of the density matrix. This expansion breaks rapidly down above threshold. This can be improved with an alternative approach, not restricted to weak coupling: the Lindblad operators are expanded in orthogonal polynomials adapted to the probability distribution for the atom-laser interaction time. Results for the photon statistics and the laser linewidth illustrate the theory.

C. Henkel

2007-05-06T23:59:59.000Z

309

Aerogel composites using chemical vapor infiltration  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Aerogel composites using chemical vapor infiltration Aerogel composites using chemical vapor infiltration Title Aerogel composites using chemical vapor infiltration Publication Type Journal Article Year of Publication 1995 Authors Hunt, Arlon J., Michael R. Ayers, and Wanqing Cao Journal Journal of Non-Crystalline Solids Volume 185 Pagination 227-232 Abstract A new method to produce novel composite materials based on the use of aerogels as a starting material is described. Using chemical vapor infiltration, a variety of solid materials were thermally deposited into the open pore structure of aerogel. The resulting materials possess new and unusual properties including photoluminescence, magnetism and altered optical properties. An important characteristic of this preparation process is the very small size of the deposits that gives rise to new behaviors. Silicon deposits exhibit photoluminescence, indicating quantum confinement. Two or more phases may be deposited simultaneously and one or both chemically or thermally reacted to produce new structures.

310

Chemical vapor detection using nanomechanical platform  

Science Journals Connector (OSTI)

For high sensitive and multiplexed chemical analysis, an opto-mechanical detection platform has been built. To check the performance of the platform, we performed water vapor response measurements for ... sensors...

S. H. Lim

2007-11-01T23:59:59.000Z

311

Chemical vapor deposition of functionalized isobenzofuran polymers  

E-Print Network [OSTI]

This thesis develops a platform for deposition of polymer thin films that can be further tailored by chemical surface modification. First, we explore chemical vapor deposition of functionalized isobenzofuran films using ...

Olsson, Ylva Kristina

2007-01-01T23:59:59.000Z

312

Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser fields: An ab initio self-interaction-free time-dependent density-functional approach  

E-Print Network [OSTI]

We present an ab initio nonpertubative investigation of the mechanisms responsible for the production of very-high-order harmonic generation (HHG) from Ar atoms and Ar+ ions by means of the self-interaction-free time-dependent density...

Carrera, Juan J.; Chu, Shih-I; Tong, X. M.

2005-06-21T23:59:59.000Z

313

Laser-optic Measurements of Velocity of Particles in the Powder Stream at Coaxial Laser Cladding  

Science Journals Connector (OSTI)

Abstract The problems of particle velocity and temperature measurement can be solved with commonly-known methods of registration based on spectrometry and a complex of laser and optical means. The diagnostic technique combines two independent methods of particle velocity measurement, namely the passive way which is based on the intrinsic radiation of the heated particles in a gas flow, and the active one which utilizes the effect of the laser beam scattering. It is demonstrated that the laser radiation can affect significantly the particles velocity at the laser cladding. Presented bar charts of statistical distributions of the particles velocities illustrate two modes of the coaxial nozzle performance, with and without ??2-laser radiation. Different types of powders (Al2O3, Mo, Ni, Al) were used in tests, the particle size distributions were typical for the laser cladding; air, nitrogen, argon were used as working gases, continuous radiation of the ??2 laser reached 3 kW. It is shown that in the laser-radiation field, the powder particles undergo extra acceleration due to the laser evaporation and reactive force occurrence resulting from the recoil pressure vapors from the beamed part of particles’ surfaces. The observed effect of particles acceleration depends on the particles concentration in the powder flow. Due to the laser acceleration, the velocities of individual particles may reach the values of about 80 – 100 m/s. The trichromatic pyrometry method was utilized to measure the particles temperature in the powder flow.

D.V. Sergachev; A.A. Mikhal’chenko; O.B. Kovalev; V.I. Kuz’min; G.N. Grachev; P.A. Pinaev

2014-01-01T23:59:59.000Z

314

Vapor Power Systems MAE 4263 Final Exam  

E-Print Network [OSTI]

Vapor Power Systems MAE 4263 Final Exam Wednesday, May 5, 2004 Prof. P.M. Moretti Key Instructions, then think, then write! 1. What is the dewpoint of the exhaust of your car, if the gasoline consists2 so that the mole fraction of water vapor is yH2 O = 9 9 + 8 + 47 = 0:14063 pH2 O = 0:14063 14

315

Laser ignition  

DOE Patents [OSTI]

In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In a third embodiment, alternating short and long pulses of light from the excitation light source are directed into the ignitor laser. Each of the embodiments of the invention can be multiplexed so as to provide laser light energy sequentially to more than one ignitor laser.

Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

2003-01-01T23:59:59.000Z

316

Applied Physics B28, 2/3 239 cw Ion Lasers Pumpedby Electron Beams  

E-Print Network [OSTI]

Applied Physics B28, 2/3 239 cw Ion Lasers Pumpedby Electron Beams J. J. Rocca, J. D. Meyer, Zeng, and As by exciting He metal-vapor mixtures with a dc electron beam. The beam is generated by glow discharge electron obtained using electron beam excitation. The conventional manner of exciting cw ion lasers is to use

Rocca, Jorge J.

317

Optical monitor for water vapor concentration  

DOE Patents [OSTI]

A system for measuring and monitoring water vapor concentration in a sample uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to a water vapor absorption line. In a preferred embodiment, the argon line is split by a magnetic field parallel to the direction of light propagation from the lamp into sets of components of downshifted and upshifted frequencies of approximately 1575 Gauss. The downshifted components are centered on a water vapor absorption line and are thus readily absorbed by water vapor in the sample; the upshifted components are moved away from that absorption line and are minimally absorbed. A polarization modulator alternately selects the upshifted components or downshifted components and passes the selected components to the sample. After transmission through the sample, the transmitted intensity of a component of the argon line varies as a result of absorption by the water vapor. The system then determines the concentration of water vapor in the sample based on differences in the transmitted intensity between the two sets of components. In alternative embodiments alternate selection of sets of components is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to the emitting plasma. 5 figs.

Kebabian, P.

1998-06-02T23:59:59.000Z

318

Optical monitor for water vapor concentration  

DOE Patents [OSTI]

A system for measuring and monitoring water vapor concentration in a sample uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to a water vapor absorption line. In a preferred embodiment, the argon line is split by a magnetic field parallel to the direction of light propagation from the lamp into sets of components of downshifted and upshifted frequencies of approximately 1575 Gauss. The downshifted components are centered on a water vapor absorption line and are thus readily absorbed by water vapor in the sample; the upshifted components are moved away from that absorption line and are minimally absorbed. A polarization modulator alternately selects the upshifted components or downshifted components and passes the selected components to the sample. After transmission through the sample, the transmitted intensity of a component of the argon line varies as a result of absorption by the water vapor. The system then determines the concentration of water vapor in the sample based on differences in the transmitted intensity between the two sets of components. In alternative embodiments alternate selection of sets of components is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to the emitting plasma.

Kebabian, Paul (Acton, MA)

1998-01-01T23:59:59.000Z

319

REPORT ON ATOMIZATION TESTS FOR PROJECT TITLED - BIODIESEL BLENDS IN MICROTURBINE.  

SciTech Connect (OSTI)

The injectors for the Capstone turbine have the general design shown in figure 1 below. It consists of an airblast atomizer with a cylindrical fuel nozzle and an annular air passage surrounding it. The airblast atomizer is surrounded by a 'mixing tube' with circular holes just downstream of the atomizer outlet and swirler holes further downstream. During operation, these holes bring 'hot' air/gases to help vaporize and provide premixed fuel and air for combustion downstream of the 'mixing' tube.

KRISHNA,C.R.

2007-01-01T23:59:59.000Z

320

Molecular Beam Studies of Hot Atom Chemical Reactions: Reactive Scattering of Energetic Deuterium Atoms  

DOE R&D Accomplishments [OSTI]

A brief review of the application of the crossed molecular beams technique to the study of hot atom chemical reactions in the last twenty years is given. Specific emphasis is placed on recent advances in the use of photolytically produced energetic deuterium atoms in the study of the fundamental elementary reactions D + H{sub 2} -> DH + H and the substitution reaction D + C{sub 2}H{sub 2} -> C{sub 2}HD + H. Recent advances in uv laser and pulsed molecular beam techniques have made the detailed study of hydrogen atom reactions under single collision conditions possible.

Continetti, R. E.; Balko, B. A.; Lee, Y. T.

1989-02-00T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Vapor Pressures and Vaporization, Sublimation, and Fusion Enthalpies of Some Fatty Acids  

E-Print Network [OSTI]

Vapor Pressures and Vaporization, Sublimation, and Fusion Enthalpies of Some Fatty Acids Joe A. Wilson and James S. Chickos* Department of Chemistry and Biochemistry, University of MissouriSt. Louis, St. Louis, Missouri 63121, United States *S Supporting Information ABSTRACT: Sublimation enthalpies

Chickos, James S.

322

Vapor Pressures and Vaporization Enthalpies of a Series of Dialkyl Phthalates by Correlation Gas Chromatography  

E-Print Network [OSTI]

Chromatography Chase Gobble and James Chickos* Department of Chemistry and Biochemistry University of Missouri-St. Louis, St. Louis Missouri 63121, United States Sergey P. Verevkin Department of Physical Chemistry: Experimental vapor pressures, vaporization, fusion and sublimation enthalpies of a number of dialkyl

Chickos, James S.

323

Laser ignition  

DOE Patents [OSTI]

In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones. In the embodiment of the invention claimed herein, the beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being combined with either the first portion after a delay before injection into the ignitor laser.

Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

2002-01-01T23:59:59.000Z

324

Optica Applicata Vol. XXVIII, No. 3, str. 239, 1998 Magneto-Optical Trap for Rubidium Atoms  

E-Print Network [OSTI]

1 Optica Applicata Vol. XXVIII, No. 3, str. 239, 1998 Magneto-Optical Trap for Rubidium Atoms Jerzy of the lasers used in the set-up. 1. Introduction Atomic physics has noticed recently a rapid development of research on different methods of cooling and trapping of atoms with use of optical forces (light pressure

325

Measuring atomic properties with an atom interferometer  

E-Print Network [OSTI]

Two experiments are presented which measure atomic properties using an atom interferometer. The interferometer splits the sodium de Broglie wave into two paths, one of which travels through an interaction region. The paths ...

Roberts, Tony David, 1972-

2002-01-01T23:59:59.000Z

326

Laser ignition  

DOE Patents [OSTI]

In the apparatus of the invention, a first excitation laser or other excitation light source capable of producing alternating beams of light having different wavelengths is used in tandem with one or more ignitor lasers to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using the single remote excitation light source for pumping one or more small lasers located proximate to one or more fuel combustion zones with alternating wavelengths of light.

Early, James W. (Los Alamos, NM); Lester, Charles S. (San Juan Pueblo, NM)

2002-01-01T23:59:59.000Z

327

Superradiant Raman Laser Magnetometer  

E-Print Network [OSTI]

We demonstrate a proof-of-principle magnetometer that relies on the active oscillation of a cold atom Raman laser to continuously map a field-sensitive atomic phase onto the phase of the radiated light. We demonstrate wideband sensitivity during continuous active oscillation, as well as narrowband sensitivity in passive Ramsey-like mode with translation of the narrowband detection in frequency using spin-echo techniques. The sensor operates with a sensitivity of 190 pT/Hz^(1/2) at 1 kHz and effective sensing volume of 2 * 10^-3 mm^3. Fundamental quantum limits on the magnetic field sensitivity of an ideal detector are also considered.

Weiner, Joshua M; Bohnet, Justin G; Chen, Zilong; Thompson, James K

2012-01-01T23:59:59.000Z

328

In situ laser processing in a scanning electron microscope  

SciTech Connect (OSTI)

Laser delivery probes using multimode fiber optic delivery and bulk focusing optics have been constructed and used for performing materials processing experiments within scanning electron microscope/focused ion beam instruments. Controlling the current driving a 915-nm semiconductor diode laser module enables continuous or pulsed operation down to sub-microsecond durations, and with spot sizes on the order of 50 {micro}m diameter, achieving irradiances at a sample surface exceeding 1 MW/cm{sup 2}. Localized laser heating has been used to demonstrate laser chemical vapor deposition of Pt, surface melting of silicon, enhanced purity, and resistivity via laser annealing of Au deposits formed by electron beam induced deposition, and in situ secondary electron imaging of laser induced dewetting of Au metal films on SiO{sub x}.

Roberts, Nicholas [University of Tennessee, Knoxville (UTK); Fowlkes, Jason Davidson [ORNL; Rack, Prof. Philip [University of Tennessee, Knoxville (UTK); Moore, Tom [OmniProbe, Inc.; Magel, Greg [OmniProbe, Inc.; Hartfield, Cheryl [OmniProbe, Inc.

2012-01-01T23:59:59.000Z

329

In situ laser processing in a scanning electron microscope  

SciTech Connect (OSTI)

Laser delivery probes using multimode fiber optic delivery and bulk focusing optics have been constructed and used for performing materials processing experiments within scanning electron microscope/focused ion beam instruments. Controlling the current driving a 915-nm semiconductor diode laser module enables continuous or pulsed operation down to sub-microsecond durations, and with spot sizes on the order of 50 {mu}m diameter, achieving irradiances at a sample surface exceeding 1 MW/cm{sup 2}. Localized laser heating has been used to demonstrate laser chemical vapor deposition of Pt, surface melting of silicon, enhanced purity, and resistivity via laser annealing of Au deposits formed by electron beam induced deposition, and in situ secondary electron imaging of laser induced dewetting of Au metal films on SiO{sub x}.

Roberts, Nicholas A.; Magel, Gregory A.; Hartfield, Cheryl D.; Moore, Thomas M.; Fowlkes, Jason D.; Rack, Philip D. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States) and Omniprobe, Inc., an Oxford Instruments Company, 10410 Miller Rd., Dallas, Texas 75238 (United States); Omniprobe, Inc., an Oxford Instruments Company, 10410 Miller Rd., Dallas, Texas 75238 (United States); Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996 (United States) and Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

2012-07-15T23:59:59.000Z

330

Recoil-induced subradiance in an ultracold atomic gas  

SciTech Connect (OSTI)

Subradiance, i.e., the cooperative inhibition of spontaneous emission by destructive interatomic interference, can be realized in a cold atomic sample confined in a ring cavity and lightened by a two-frequency laser. The atoms, scattering the photons of the two laser fields into the cavity mode, recoil and change their momentum. Under proper conditions the atomic initial momentum state and the first two momentum recoil states form a three-level degenerate cascade. A stationary subradiant state is obtained after the scattered photons have left the cavity, leaving the atoms in a coherent superposition of the three collective momentum states. Both a semiclassical description of the process and the quantum subradiant state with its Wigner function are given. Antibunching, quantum correlations, and entanglement between the atomic modes of the subradiant state are demonstrated.

Cola, M. M.; Bigerni, D.; Piovella, N. [Dipartimento di Fisica, Universita degli Studi di Milano and INFN Sezione di Milano, Via Celoria 16, Milano I-20133 (Italy)

2009-05-15T23:59:59.000Z

331

Analytical model of an isolated single-atom electron source  

Science Journals Connector (OSTI)

Abstract An analytical model of a single-atom electron source is presented, where electrons are created by near-threshold photoionization of an isolated atom. The model considers the classical dynamics of the electron just after the photon absorption, i.e. its motion in the potential of a singly charged ion and a uniform electric field used for acceleration. From closed expressions for the asymptotic transverse electron velocities and trajectories, the effective source temperature and the virtual source size can be calculated. The influence of the acceleration field strength and the ionization laser energy on these properties has been studied. With this model, a single-atom electron source with the optimum electron beam properties can be designed. Furthermore, we show that the model is also applicable to ionization of rubidium atoms, and thus also describes the ultracold electron source, which is based on photoionization of laser-cooled alkali atoms.

W.J. Engelen; E.J.D. Vredenbregt; O.J. Luiten

2014-01-01T23:59:59.000Z

332

Theory and Experiments Relating to the Striated Glow Discharge in Mercury Vapor  

Science Journals Connector (OSTI)

Theory of the glow discharge in a monatomic gas.—For the case of parallel plane electrodes with a hot cathode as source of electrons, the potential distribution and ion concentration in the Crookes dark space, negative glow, Faraday dark space and positive column are shown to be predictable from considerations of space charge and of ionization and excitation of the gas. While with weak currents there is a negative space charge throughout, sufficiently intense ionization is shown to lead to a cathode drop, followed by a region of reversed electric field in which positive ions and electrons both move toward the anode by diffusion, owing to their large concentration gradient. Still farther from the cathode the field changes to its normal direction and increases up to the positive column. In the positive column the field and concentration are uniform unless atoms excited by electron impacts in certain layers are prevented from diffusing between the layers, when striations may be obtained with periodic changes of field and of concentration. The cathode edge of each striation has a positive space charge. The theory of the arc discharge is essentially the same, the arc being simply the negative glow of the longer glow discharge.Glow discharge in mercury vapor.—Various predictions of the above theory were verified by experiments with Hg vapor in vacuum tubes provided with hot cathodes. (1) Potential distribution and ion concentration were investigated by Langmuir's modified probe method and found to agree with the theoretical deductions, except that the concentration of positive ions in the positive column comes out too large. This result indicates the presence of negative mercury ions. (2) The distribution of velocities of electrons is Maxwellian except between striations. (3) The emission of light seems associated more with excitation by electron collision than with ionization and recombination. (4) Conditions for existence of striations. Striations are not found in pure Hg vapor unless the current is small or some substance like H2 is introduced to remove excited atoms. (5) The presence of atomic hydrogen which should be produced in the process of removing excited Hg atoms was proved by use of tungsten oxide. (6) Introduction of He, which cannot remove excited atoms, does not tend to produce striations. (7) The relative concentrations of excited atoms was determined from the optical absorption of subordinate series Hg lines. It was found that excited atoms exist in striations but not in the regions between, and are more numerous if the amount of H2 impurity is reduced.Band spectrum of HgH seems associated with the action of excited Hg atoms on hydrogen, and is emitted as a result of inelastic collisions in striations.

K. T. Compton; Louis A. Turner; W. H. McCurdy

1924-12-01T23:59:59.000Z

333

ARM - Field Campaign - Water Vapor IOP  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

govCampaignsWater Vapor IOP govCampaignsWater Vapor IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Water Vapor IOP 1996.09.10 - 1996.09.30 Lead Scientist : Henry Revercomb For data sets, see below. Summary SCHEDULE This IOP will be conducted from September 10 - 30, 1996 (coincident with the Fall ARM-UAV IOP). Instruments that do not require supervision will be operated continuously during this period. Instruments that do require supervision are presently planned to be operated for 8-hour periods each day. Because it is necessary to cover as broad a range of environmental conditions as possible, the daily 8-hour period will be shifted across the diurnal cycle as deemed appropriate during the IOP (but will be maintained as a contiguous 8-hour block).

334

atmospheric water vapor | OpenEI  

Open Energy Info (EERE)

atmospheric water vapor atmospheric water vapor Dataset Summary Description (Abstract): Monthly Average Solar Resource for 2-axis tracking concentrating collectors for Mexico, Central America, and the Caribbean Islands. (Purpose): Provide information on the solar resource potential for the data domain. The insolation values represent the average solar energy available to a concentrating collector, such as a dish collector, which tracks the sun continuously. Source NREL Date Released July 31st, 2006 (8 years ago) Date Updated October 30th, 2007 (7 years ago) Keywords atmospheric water vapor Carribean Islands Central America DNI GIS Mexico NREL GEF solar SWERA UNEP Data application/zip icon Download Shapefile (zip, 247.8 KiB) text/csv icon Download Data (csv, 370.6 KiB) Quality Metrics Level of Review Some Review

335

atmoshperic water vapor | OpenEI  

Open Energy Info (EERE)

atmoshperic water vapor atmoshperic water vapor Dataset Summary Description (Abstract): Monthly Average Solar Resource for flat-plate collectors tilted at latitude for China. Source NREL Date Released April 12th, 2005 (9 years ago) Date Updated October 30th, 2007 (7 years ago) Keywords atmoshperic water vapor China GEF GIS NREL solar SWERA TILT UNEP Data application/zip icon Download Shapefile (zip, 625.6 KiB) text/csv icon Download Data (csv, 704.1 KiB) Quality Metrics Level of Review Some Review Comment Temporal and Spatial Coverage Frequency Time Period 01/01/1985 - 12/31/1991 License License Open Data Commons Public Domain Dedication and Licence (PDDL) Comment Rate this dataset Usefulness of the metadata Average vote Your vote Usefulness of the dataset Average vote Your vote Ease of access

336

Vapor characterization of Tank 241-C-103  

SciTech Connect (OSTI)

The Westinghouse Hanford Company Tank Vapor Issue Resolution Program has developed, in cooperation with Northwest Instrument Systems, Inc., Oak Ridge National Laboratory, Oregon Graduate Institute of Science and Technology, Pacific Northwest Laboratory, and Sandia National Laboratory, the equipment and expertise to characterize gases and vapors in the high-level radioactive waste storage tanks at the Hanford Site in south central Washington State. This capability has been demonstrated by the characterization of the tank 241-C-103 headspace. This tank headspace is the first, and for many reasons is expected to be the most problematic, that will be characterized (Osborne 1992). Results from the most recent and comprehensive sampling event, sample job 7B, are presented for the purpose of providing scientific bases for resolution of vapor issues associated with tank 241-C-103. This report is based on the work of Clauss et al. 1994, Jenkins et al. 1994, Ligotke et al. 1994, Mahon et al. 1994, and Rasmussen and Einfeld 1994. No attempt has been made in this report to evaluate the implications of the data presented, such as the potential impact of headspace gases and vapors to tank farm workers health. That and other issues will be addressed elsewhere. Key to the resolution of worker health issues is the quantitation of compounds of toxicological concern. The Toxicology Review Panel, a panel of Pacific Northwest Laboratory experts in various areas, of toxicology, has chosen 19 previously identified compounds as being of potential toxicological concern. During sample job 7B, the sampling and analytical methodology was validated for this preliminary list of compounds of toxicological concern. Validation was performed according to guidance provided by the Tank Vapor Conference Committee, a group of analytical chemists from academic institutions and national laboratories assembled and commissioned by the Tank Vapor Issue Resolution Program.

Huckaby, J.L. [Westinghouse Hanford Co., Richland, WA (United States); Story, M.S. [Northwest Instrument Systems, Inc. Richland, WA (United States)

1994-06-01T23:59:59.000Z

337

A QSPR Study of the Solubility of Gases and Vapors in Water  

Science Journals Connector (OSTI)

QSPR correlation equations were developed for the prediction of the solubilities of organic gases and vapors in water. ... The Ostwald solubility coefficient (L) is defined as the ratio of the equilibrium concentrations of a gaseous compound in the liquid and in the gas phase (eq 1), where a superscript w (Lw) usually denotes water as a solvent. ... Table 2) are as follows:? the energy gap between HOMO and LUMO (EHOMO ? ELUMO), the numbers of nitrogen atoms and of oxygen atoms in the molecule, and the most negative partial charge weighted topological electronic index43a (PCWTE) defined by eq 7, where qi and qj are the Zefirov partial charges43b of the bonded atoms, rij is the respective bond lengths, and Qmin is the most negative partial charge. ...

Alan R. Katritzky; Lan Mu; Mati Karelson

1996-11-21T23:59:59.000Z

338

Thermal electric vapor trap arrangement and method  

DOE Patents [OSTI]

A technique for trapping vapor within a section of a tube is disclosed herein. This technique utilizes a conventional, readily providable thermal electric device having a hot side and a cold side and means for powering the device to accomplish this. The cold side of this device is positioned sufficiently close to a predetermined section of the tube and is made sufficiently cold so that any condensable vapor passing through the predetermined tube section is condensed and trapped, preferably within the predetermined tube section itself. 4 figs.

Alger, T.

1988-03-15T23:59:59.000Z

339

Laser device  

DOE Patents [OSTI]

A laser device includes a virtual source configured to aim laser energy that originates from a true source. The virtual source has a vertical rotational axis during vertical motion of the virtual source and the vertical axis passes through an exit point from which the laser energy emanates independent of virtual source position. The emanating laser energy is collinear with an orientation line. The laser device includes a virtual source manipulation mechanism that positions the virtual source. The manipulation mechanism has a center of lateral pivot approximately coincident with a lateral index and a center of vertical pivot approximately coincident with a vertical index. The vertical index and lateral index intersect at an index origin. The virtual source and manipulation mechanism auto align the orientation line through the index origin during virtual source motion.

Scott, Jill R. (Idaho Falls, ID); Tremblay, Paul L. (Idaho Falls, ID)

2008-08-19T23:59:59.000Z

340

Elements & Compounds Atoms (Elements)  

E-Print Network [OSTI]

#12;Elements & Compounds #12;Atoms (Elements) Molecules (Compounds) Cells Elements & Compounds #12;Nucleus Electrons Cloud of negative charge (2 electrons) Fig. 2.5: Simplified model of a Helium (He) Atom He 4.002602 2 Helium Mass Number (~atomic mass) = number of Neutrons + Protons = 4 for Helium Atomic

Frey, Terry

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Investigations of chemical vapor deposition of GaN using synchrotron radiation  

SciTech Connect (OSTI)

The authors apply synchrotron x-ray analysis techniques to probe the surface structure of GaN films during synthesis by metal-organic chemical vapor deposition (MOCVD). Their approach is to observe the evolution of surface structure and morphology in real time using grazing incidence x-ray scattering (GIXS). This technique combines the ability of x-rays to penetrate the chemical vapor deposition environment for in situ measurements, with the sensitivity of GIXS to atomic scale structure. In this paper they present examples from some of their studies of growth modes and surface evolution as a function of process conditions that illustrate the capabilities of synchrotron x-ray analysis during MOCVD growth. They focus on studies of the homoepitaxial growth mode, island coarsening dynamics, and effects of impurities.

Thompson, C.; Stephenson, G. B.; Eastman, J. A.; Munkholm, A.; Auciello, O.; Murty, M. V. R.; Fini, P.; DenBaars, S. P.; Speck, J. S.

2000-05-25T23:59:59.000Z

342

Ultrafast X-ray Absorption Spectroscopy using Laser-Driven Electron X-ray Sources (LEXS)  

E-Print Network [OSTI]

: ultrafast x-rays, x-ray absorption spectroscopy, terawatt lasers, ultrafast reaction dynamics, atomic motion atomic motion by scrutinizing the changes in x- ray absorption spectra during reactions. FirstUltrafast X-ray Absorption Spectroscopy using Laser-Driven Electron X-ray Sources (LEXS) Guangjun

Guo, Ting

343

Selective Deuterium Ion Acceleration Using the Vulcan PW Laser  

E-Print Network [OSTI]

We report on the successful demonstration of selective acceleration of deuterium ions by target-normal sheath acceleration (TNSA) with a high-energy petawatt laser. TNSA typically produces a multi-species ion beam that originates from the intrinsic hydrocarbon and water vapor contaminants on the target surface. Using the method first developed by Morrison, et al., \\cite{Morrison:POP2012} an ion beam with $>$99$\\%$ deuterium ions and peak energy 28 MeV is produced with a 200 J, 700fs, $>10^{20} W/cm^{2}$ laser pulse by cryogenically freezing heavy water (D$_{2}$O) vapor onto the rear surface of the target prior to the shot. The estimated total yield of deuterium ions in an assumed 10$^{\\circ}$ half-angle cone was 3.0 $\\mu$C (1.9 $\\times 10^{13}$ ions) with 6.6$\\%$ laser-to-deuterium ion energy conversion efficiency.

Krygier, AG; Kar, S; Ahmed, H; Alejo, A; Clarke, R; Fuchs, J; Green, A; Jung, D; Kleinschmidt, A; Najmudin, Z; Nakamura, H; Norreys, P; Notley, M; Oliver, M; Roth, M; Vassura, L; Zepf, M; Borghesi, M; Freeman, RR

2015-01-01T23:59:59.000Z

344

Environmental Chemistry at Vapor/Water Interfaces  

E-Print Network [OSTI]

Environmental Chemistry at Vapor/Water Interfaces: Insights from Vibrational Sum Frequency Generation Spectroscopy Aaron M. Jubb, Wei Hua, and Heather C. Allen Department of Chemistry, The Ohio State/0505-0107$20.00 Keywords salts, lipids, atmospheric chemistry, ion binding, oxidation Abstract The chemistry that occurs

345

Advancing Explosives Detection Capabilities: Vapor Detection  

ScienceCinema (OSTI)

A new, PNNL-developed method provides direct, real-time detection of trace amounts of explosives such as RDX, PETN and C-4. The method selectively ionizes a sample before passing the sample through a mass spectrometer to detect explosive vapors. The method could be used at airports to improve aviation security.

Atkinson, David

2014-07-24T23:59:59.000Z

346

Program performs vapor-liquid equilibrium calculations  

SciTech Connect (OSTI)

A program designed for the Hewlett-Packard HP-41CV or 41C calculators solves basic vapor-liquid equilibrium problems, including figuring the dewpoint, bubblepoint, and equilibrium flash. The algorithm uses W.C. Edmister's method for predicting ideal-solution K values.

Rice, V.L.

1982-06-28T23:59:59.000Z

347

Synchroton X-Ray Studies of Liquid-Vapor Interfaces  

Science Journals Connector (OSTI)

The variation of density across the liquid-vapor interface from essentially zero density far out in the vapor phase to a homogeneous density deep in the liquid phase can be determined by X-ray reflectivity mea...

J. Als-Nielsen

1988-01-01T23:59:59.000Z

348

Vapor intrusion modeling : limitations, improvements, and value of information analyses  

E-Print Network [OSTI]

Vapor intrusion is the migration of volatile organic compounds (VOCs) from a subsurface source into the indoor air of an overlying building. Vapor intrusion models, including the Johnson and Ettinger (J&E) model, can be ...

Friscia, Jessica M. (Jessica Marie)

2014-01-01T23:59:59.000Z

349

Estimating the Atmospheric Water Vapor Content from Sun Photometer Measurements  

Science Journals Connector (OSTI)

The differential absorption technique for estimating columnar water vapor values from the analysis of sunphotometric measurements with wide- and narrowband interferential filters centered near 0.94 ?m is discussed and adapted. Water vapor line ...

Artemio Plana-Fattori; Michel Legrand; Didier Tanré; Claude Devaux; Anne Vermeulen; Philippe Dubuisson

1998-08-01T23:59:59.000Z

350

OPTIMIZATION OF INJECTION INTO VAPOR-DOMINATED GEOTHERMAL  

E-Print Network [OSTI]

given by U.S. Department of Energy, Geothermal Division. #12;vii Table of Contents ABSTRACTOPTIMIZATION OF INJECTION INTO VAPOR-DOMINATED GEOTHERMAL RESERVOIRS CONSIDERING ADSORPTION governing the behavior of vapor- dominated geothermal reservoirs. These mechanisms affect both

Stanford University

351

Neutral atom traps.  

SciTech Connect (OSTI)

This report describes progress in designing a neutral atom trap capable of trapping sub millikelvin atom in a magnetic trap and shuttling the atoms across the atom chip from a collection area to an optical cavity. The numerical simulation and atom chip design are discussed. Also, discussed are preliminary calculations of quantum noise sources in Kerr nonlinear optics measurements based on electromagnetically induced transparency. These types of measurements may be important for quantum nondemolition measurements at the few photon limit.

Pack, Michael Vern

2008-12-01T23:59:59.000Z

352

Laser program annual report, 1979  

SciTech Connect (OSTI)

This volume contains four sections that covers the areas of target design, target fabrication, diagnostics, and experiments. Section 3 reports on target design activities, plasma theory and simulation, code development, and atomic theory. Section 4 presents the accomplishments of the target fabrication group, and Section 5 presents results of diagnostic developments and applications for the year. The results of laser-target experiments are presented. (MOW)

Coleman, L.W.; Strack, J.R. (eds.)

1980-03-01T23:59:59.000Z

353

Laser goniometer  

DOE Patents [OSTI]

The laser goniometer is an apparatus which permits an operator to sight along a geologic feature and orient a collimated lamer beam to match the attitude of the feature directly. The horizontal orientation (strike) and the angle from horizontal (dip), are detected by rotary incremental encoders attached to the laser goniometer which provide a digital readout of the azimuth and tilt of the collimated laser beam. A microprocessor then translates the square wave signal encoder outputs into an ASCII signal for use by data recording equipment.

Fairer, George M. (Boulder, CO); Boernge, James M. (Lakewood, CO); Harris, David W. (Lakewood, CO); Campbell, DeWayne A. (Littleton, CO); Tuttle, Gene E. (Littleton, CO); McKeown, Mark H. (Golden, CO); Beason, Steven C. (Lakewood, CO)

1993-01-01T23:59:59.000Z

354

A superradiant clock laser on a magicwavelength optical lattice  

E-Print Network [OSTI]

An ideal superradiant laser on an optical clock transition of noninteracting cold atoms is predicted to exhibit an extreme frequency stability and accuracy far below mHz-linewidth. In any concrete setup sufficiently many atoms have to be confined and pumped within a finite cavity mode volume. Using a magic wavelength lattice minimizes light shifts and allows for almost uniform coupling to the cavity mode. Never- theless, the atoms are subject to dipole-dipole interaction and collective spontaneous decay which compromises the ultimate frequency stability. In the high density limit the Dicke superradiant linewidth enhancement will broaden the laser line and nearest neighbor couplings will induce shifts and fluctuations of the laser frequency. We estimate the magnitude and scaling of these effects by direct numerical simulations of few atom systems for different geometries and densities. For Strontium in a regularly filled magic wavelength configuration atomic interactions induce small laser frequency shifts only and collective spontaneous emission weakly broadens the laser. These interactions generally enhance the laser sensitivity to cavity length fluctuations but for optimally chosen operating conditions can lead to an improved synchronization of the atomic dipoles.

Thomas Maier; Sebastian Kraemer; Laurin Ostermann; Helmut Ritsch

2014-02-19T23:59:59.000Z

355

Apparent Temperature Dependence on Localized Atmospheric Water Vapor  

E-Print Network [OSTI]

Apparent Temperature Dependence on Localized Atmospheric Water Vapor Matthew Montanaroa, Carl), hence water vapor is the primary constituent of concern. The tower generates a localized water vapor, Office B108, Aiken, SC, USA ABSTRACT The atmosphere is a critical factor in remote sensing. Radiance from

Salvaggio, Carl

356

Laser-Induced Breakdown Spectroscopy System Using a Passively Q-Switched Laser  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser-Induced Breakdown Spectroscopy System Laser-Induced Breakdown Spectroscopy System Using a Passively Q-Switched Laser Opportunity Research is active on the patent-pending technology, titled "Laser-Induced Breakdown Spectroscopy (LIBS) System Using a Passively Q-Switched Laser." This technology is available for licensing and/or further collaborative research from the U.S. Department of Energy's National Energy Technology Laboratory. Overview Atomic spectroscopy systems such as LIBS are used in many applications where the elemental composition of a solid, liquid or gas sample is desired. In addition, this detection technology has the advantage of providing composition data without sample destruction. In LIBS systems, precise timing and control between the laser and the spectrometer detector are

357

Drop shaping by laser-pulse impact  

E-Print Network [OSTI]

We study the hydrodynamic response of a falling drop hit by a laser pulse. Combining high-speed with stroboscopic imaging we report that a millimeter-sized dyed water drop hit by a milli-Joule nanosecond laser-pulse deforms and propels forward at several meters per second, until it eventually fragments. We show that the drop motion results from the recoil momentum imparted at the drop surface by water vaporization. We measure the propulsion speed and the time-deformation law of the drop, complemented by boundary integral simulations. We explain the drop propulsion and shaping in terms of the laser pulse energy and drop surface tension. These findings are crucial for the generation of extreme ultraviolet (EUV) light in lithography machines.

Klein, Alexander L; Visser, Claas Willem; Lhuissier, Henri; Sun, Chao; Snoeijer, Jacco H; Villermaux, Emmanuel; Lohse, Detlef; Gelderblom, Hanneke

2015-01-01T23:59:59.000Z

358

Pulsed Laser Deposition | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Pulsed Laser Deposition Pulsed Laser Deposition EMSL's pulsed laser deposition (PLD) system is designed for epitaxial growth of oxide, ceramic, or synthetic mineral thin films and...

359

Laser barometer  

SciTech Connect (OSTI)

This paper describes an invention of a pressure measuring instrument which uses laser radiation to sense the pressure in an enclosed environment by means of measuring the change in refractive index of a gas - which is pressure dependent.

Abercrombie, K.R.; Shiels, D.; Rash, T.

1998-04-01T23:59:59.000Z

360

LASER ACCELERATORS  

E-Print Network [OSTI]

UNIVERSITY OF CALIFORNIA Accelerator & Fusion Researchat the 1983 Particle Accelerator Conference, Santa Fe, NM,March 21-23, 1983 LASER ACCELERATORS A.M. Sessler TWO-WEEK

Sessler, A.M.

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Laser ignition  

Science Journals Connector (OSTI)

Due to their thermodynamic benefits, second-generation spark-ignition engines with gasoline direct injection systems have ... combination of a spray-guided combustion process with laser-induced ignition allows th...

Bernhard Geringer; Dominikus Klawatsch; Josef Graf; Hans Peter Lenz…

2004-03-01T23:59:59.000Z

362

In the OSTI Collections: Free-Electron Lasers | OSTI, US Dept of Energy,  

Office of Scientific and Technical Information (OSTI)

Free-Electron Lasers Free-Electron Lasers Existing Free-Electron Lasers Using Free-Electron Lasers for Measurement and Defense New Free-Electron Laser Designs References Research Organizations Reports available from OSTI's Information Bridge While most types of laser produce coherent light from electric charges bound within atoms, molecules, or solids, unbound charges are the light source in free-electron lasers. Lasers of this type can operate at higher frequencies than are easily achieved with bound-electron lasers. Various uses and designs of free-electron lasers are the focus of different projects sponsored through the Department of Energy. Lasers, like any source of light or other electromagnetic waves, produce waves when some of the electric charges they contain go from having a

363

Advanced Membrane Systems: Recovering Wasteful and Hazardous Fuel Vapors at the Gasoline Tank  

Broader source: Energy.gov [DOE]

Case study covering Compact Membrane Systems, Inc. and its membrane vapor processor that recovers fuel vapors from gasoline refueling.

364

Theory of laser-amplifier linear gain  

Science Journals Connector (OSTI)

The theory of small-signal laser amplification is developed for homogeneously broadened systems in which the three main decay rates, for the collective atomic dipole moment, the population inversion, and the field in the laser cavity, have arbitrary relative magnitudes. The calculations extend previous work on class-A and -B lasers, where the dipole decay rate greatly exceeds the other two rates, to class-C lasers, where the dipole decay rate is comparable to the others. The free-running laser is assumed to excite a single longitudinal mode of the cavity, whose frequency generally differs from that of the coupled atomic transition. The linear gains of the laser are derived for input signals whose frequencies are close to that of the lasing mode or to one of its adjacent nonlasing longitudinal modes. Divergences in the gain that occur for these two arrangements are associated with the previously studied single-mode and multimode instabilities of the free-running laser, respectively.

J. Jahanpanah and R. Loudon

1997-09-01T23:59:59.000Z

365

Drilling Large Diameter Holes in Rocks Using Multiple Laser Beams  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Drilling Large Diameter Holes in Rocks Using Multiple Laser Beams (504) Drilling Large Diameter Holes in Rocks Using Multiple Laser Beams (504) Richard Parker,. Parker Geoscience Consulting, LLC, Arvada, Colorado, USA; Zhiyue Xu and Claude Reed, Argonne National Laboratory, Argonne, Illinois, USA; Ramona Graves, Department of Petroleum Engineering, Colorado School of Mines, Golden, Colorado, USA; Brian Gahan and Samih Batarseh, Gas Technology Institute, Des Plaines, Illinois, USA ABSTRACT Studies on drilling petroleum reservoir rocks with lasers show that modern infrared lasers have the capability to spall (thermally fragment), melt and vaporize natural earth materials with the thermal spallation being the most efficient rock removal mechanism. Although laser irradiance as low as 1000 W/cm 2 is sufficient to spall rock, firing the

366

TWO-DIMENSIONAL MODELING OF LASER SPALLATION DRILLING OF ROCKS  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

DIMENSIONAL MODELING OF LASER SPALLATION DRILLING OF ROCKS DIMENSIONAL MODELING OF LASER SPALLATION DRILLING OF ROCKS P532 Zhiyue Xu, Yuichiro Yamashita 1 , and Claude B. Reed Argonne National Laboratory, Argonne, IL 60439, USA 1 Now with Kyushu University, Japan Abstract High power lasers can weaken, spall, melt and vaporize natural earth materials with thermal spallation being the most energy efficient rock removal mechanism. Laser rock spallation is a very complex phenomenon that depends on many factors. Computer numerical modeling would provides great tool to understand the fundamental of this complex phenomenon, which is crucial to the success of its applications. Complexity of modeling laser rock spallation is due to: 1) rock is a porous media, to which traditional theories of heat transfer and rock mechanics can not be directly

367

Laser EYE SURGERY LASIK and Excimer Lasers  

E-Print Network [OSTI]

Laser EYE SURGERY LASIK and Excimer Lasers Michael Hutchins #12;The PROBLEM opia - near sightedness - Laser Assisted in SItu Keratomileusis atomileusis is the procedure of opening the eye and ring the cornea. SIK uses an excimer laser to perform the alterations an er a knife or a femtosecond laser

Fygenson, Deborah Kuchnir

368

7 -ATOMIC PROCESSES Atomic processes can be  

E-Print Network [OSTI]

1 7 - ATOMIC PROCESSES Atomic processes can be: 1. Scattering 2. Absorption/Thermal Emission scattering, although the results won't change much when this condition is relaxed. Absorption/Thermal Emission Free-free (continuum) ("Bremsstrahlung") Emission/Absorption #12;2 Bound-Bound & Bound

Sitko, Michael L.

369

7 -ATOMIC PROCESSES Atomic processes can be  

E-Print Network [OSTI]

1 7 - ATOMIC PROCESSES Atomic processes can be: 1. Scattering 2. Absorption/Thermal Emission scattering, although the results won't change much when this condition is relaxed. #12;2 Absorption/Thermal Emission Free-free (continuum) ("Bremsstrahlung") Emission/Absorption Bound-Bound & Bound-Free Processes

Sitko, Michael L.

370

Detection of single atoms by resonance ionization spectroscopy  

SciTech Connect (OSTI)

Rutherford's idea for counting individual atoms can, in principle, be implemented for nearly any type of atom, whether stable or radioactive, by using methods of resonance ionization. With the RIS technique, a laser is tuned to a wavelength which will promote a valence electron in a Z-selected atom to an excited level. Additional resonance or nonresonance photoabsorption steps are used to achieve nearly 100% ionization efficiencies. Hence, the RIS process can be saturated for the Z-selected atoms; and since detectors are available for counting either single electrons or positive ions, one-atom detection is possible. Some examples are given of one-atom detection, including that of the noble gases, in order to show complementarity with AMS methods. For instance, the detection of /sup 81/Kr using RIS has interesting applications for solar neutrino research, ice-cap dating, and groundwater dating. 39 refs., 7 figs., 2 tabs.

Hurst, G.S.

1986-01-01T23:59:59.000Z

371

Progress on a Miniature Cold-Atom Frequency Standard  

E-Print Network [OSTI]

Atomic clocks play a crucial role in timekeeping, communications, and navigation systems. Recent efforts enabled by heterogeneous MEMS integration have led to the commercial introduction of Chip-Scale Atomic Clocks (CSAC) with a volume of 16 cm3, power consumption of 120 mW, and instability (Allan Deviation) of {\\sigma}({\\tau} = 1 sec) cooled atoms. In this paper, we present results describing the development of a miniature cold-atom apparatus for operation as a frequency standard. Our architecture is based on laser-cooling a sample of neutral atoms in a Magneto-Optical Trap (MOT) using a conical retro-reflector in a miniature vacuum chamber. Trapping the atoms in vacuum and performing microwave interrogation in the dark reduces the temperature sensitivity compared to va...

Scherer, David R; Mescher, Mark; Stoner, Richard; Timmons, Brian; Rogomentich, Fran; Tepolt, Gary; Mahnkopf, Sven; Noble, Jay; Chang, Sheng; Taylor, Dwayne

2014-01-01T23:59:59.000Z

372

E-Print Network 3.0 - atomic lines isotope Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

lines isotope Search Powered by Explorit Topic List Advanced Search Sample search results for: atomic lines isotope Page: << < 1 2 3 4 5 > >> 1 Isotope selectivity in laser cooling...

373

Along the Laser Beampath  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

8 20 | Next | Last Back to Index NIF Laser Bay Each NIF laser bay is 122 meters (400 feet) long and contains 96 beamlines. This side view of Laser Bay 2 shows the four-high laser...

374

Observation of keyhole-mode laser melting in laser powder-bed fusion additive manufacturing  

Science Journals Connector (OSTI)

Abstract Laser powder-bed fusion additive manufacturing of metals employs high-power focused laser beams. Typically, the depth of the molten pool is controlled by conduction of heat in the underlying solid material. But, under certain conditions, the mechanism of melting can change from conduction to so-called “keyhole-mode” laser melting. In this mode, the depth of the molten pool is controlled by evaporation of the metal. Keyhole-mode laser melting results in melt pool depths that can be much deeper than observed in conduction mode. In addition, the collapse of the vapor cavity that is formed by the evaporation of the metal can result in a trail of voids in the wake of the laser beam. In this paper, the experimental observation of keyhole-mode laser melting in a laser powder-bed fusion additive manufacturing setting for 316L stainless steel is presented. The conditions required to transition from conduction controlled melting to keyhole-mode melting are identified.

Wayne E. King; Holly D. Barth; Victor M. Castillo; Gilbert F. Gallegos; John W. Gibbs; Douglas E. Hahn; Chandrika Kamath; Alexander M. Rubenchik

2014-01-01T23:59:59.000Z

375

Theory of a coherent atomic-beam generator  

Science Journals Connector (OSTI)

We present a many-body theory of a driven and damped trapped gas of interacting bosons, and demonstrate that one of the trap levels can become coherently populated, thereby leading to a coherent atomic-beam generator, or ‘‘laser for atoms.’’ The specific system we consider consists of a sample of bosonic atoms interacting via the near-resonant dipole-dipole interaction. The transverse center-of-mass motion of the atoms is confined by a two-dimensional potential well created by an array of cooling laser beams, while their longitudinal motion is quantized by a Fabry-Pérot for atoms. Under appropriate conditions, the dipole-dipole selection rules lead to the simplification that only two quantized levels of atomic motion need to be considered explicitly, the other levels being treated as reservoirs. One of the two levels is the ‘‘pump level,’’ while the other is the one where atomic coherence builds up (the ‘‘lasing’’ level). The master equation describing the dynamics of these levels can be solved numerically, and its solution exhibits a ‘‘threshold behavior’’ with a transition from super-Poissonian to Poissonian atom statistics in the ‘‘lasing mode.’’ © 1996 The American Physical Society.

A. M. Guzmán; M. Moore; P. Meystre

1996-02-01T23:59:59.000Z

376

Reading Comprehension - Atomic History  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Atomic History Atomic History A Greek philosopher named Democritus said that all atoms are small, hard particles. He thought that atoms were made of a single material formed into different shapes and sizes. The word " _________ element compound mixture atom " is derived from the Greek word "atomos" which means "not able to be divided." In 1803, John Dalton, a school teacher, proposed his atomic theory. Dalton's theory states that elements (substances composed of only one type of _________ molecules ions atom ) combine in certain proportions to form _________ compounds atoms mixtures elements . In 1897, a British scientist named J. J. Thomson experimented with a cathode-ray tube which had a positively charged plate. The plate attracted negatively charged particles that we now call _________ protons neutrons

377

The Universe Adventure - Atoms  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Matter and Atoms Matter and Atoms Richard Feynman "If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generations of creatures, what statement would contain the most information in the fewest words? I believe it is that...all things are made of atoms." -Richard P. Feynman, winner of the 1965 Nobel Prize in Physics All is atoms Matter is made of atoms, and atoms are comprised of protons, neutrons, and electrons. Everything in the Universe is made of matter. Though matter exists in many different forms, each form is made out of the same basic constituents: small particles called atoms. Atoms themselves are made of smaller particles: protons, neutrons, and electrons. Protons and neutrons are composed of even smaller particles called quarks.

378

February 1, 1994 / Vol. 19, No. 3 / OPTICS LETTERS Spin relaxation of optically trapped atoms by light scattering  

E-Print Network [OSTI]

February 1, 1994 / Vol. 19, No. 3 / OPTICS LETTERS Spin relaxation of optically trapped atoms of optically trapped atoms that is due to light scattering from the trap laser. We observe relaxation times greater than 2 s for ground-state hyperfine-levelpopulations of 85 Rb atoms trapped in an optical dipole

Heinzen, Daniel J.

379

Atomizing nozzle and process  

DOE Patents [OSTI]

High pressure atomizing nozzle includes a high pressure gas manifold having a divergent expansion chamber between a gas inlet and arcuate manifold segment to minimize standing shock wave patterns in the manifold and thereby improve filling of the manifold with high pressure gas for improved melt atomization. The atomizing nozzle is especially useful in atomizing rare earth-transition metal alloys to form fine powder particles wherein a majority of the powder particles exhibit particle sizes having near-optimum magnetic properties.

Anderson, I.E.; Figliola, R.S.; Molnar, H.M.

1993-07-20T23:59:59.000Z

380

Growth of graphene underlayers by chemical vapor deposition  

SciTech Connect (OSTI)

We present a simple and very convincing approach to visualizing that subsequent layers of graphene grow between the existing monolayer graphene and the copper catalyst in chemical vapor deposition (CVD). Graphene samples were grown by CVD and then transferred onto glass substrates by the bubbling method in two ways, either direct-transfer (DT) to yield poly (methyl methacrylate) (PMMA)/graphene/glass or (2) inverted transfer (IT) to yield graphene/PMMA/glass. Field emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM) were used to reveal surface features for both the DT and IT samples. The results from FE-SEM and AFM topographic analyses of the surfaces revealed the underlayer growth of subsequent layers. The subsequent layers in the IT samples are visualized as 3D structures, where the smaller graphene layers lie above the larger layers stacked in a concentric manner. The results support the formation of the so-called “inverted wedding cake” stacking in multilayer graphene growth.

Fabiane, Mopeli; Khamlich, Saleh; Bello, Abdulhakeem; Dangbegnon, Julien; Momodu, Damilola; Manyala, Ncholu, E-mail: ncholu.manyala@up.ac.za [Department of Physics, Institute of Applied Materials, SARChI Chair in Carbon Technology and Materials, University of Pretoria, Pretoria 0028 (South Africa)] [Department of Physics, Institute of Applied Materials, SARChI Chair in Carbon Technology and Materials, University of Pretoria, Pretoria 0028 (South Africa); Charlie Johnson, A. T. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)] [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

2013-11-15T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
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381

Thermodynamic pathways to melting, ablation, and solidification in absorbing solids under pulsed laser irradiation  

Science Journals Connector (OSTI)

The thermodynamic pathways involved in laser irradiation of absorbing solids are investigated in silicon for pulse durations of 500fs and 100ps. This is achieved by accounting for carrier and atom dynamics within a combined Monte Carlo and molecular-dynamics scheme and simultaneously tracking the time evolution of the irradiated material in ?-T-P space. Our simulations reveal thermal changes in long-range order and state of aggregation driven, in most cases, by nonequilibrium states of rapidly heated or promptly cooled matter. Under femtosecond irradiation near the ablation threshold, the system is originally pulled to a near-critical state following rapid (?10?12s) disordering of the mechanically unstable crystal and isochoric heating of the resulting metallic liquid. The latter is then adiabatically cooled to the liquid-vapor regime where phase explosion of the subcritical, superheated melt is initiated by a direct conversion of translational, mechanical energy into surface energy on a ?10?12–10?11s time scale. At higher fluences, matter removal involves, instead, the fragmentation of an initially homogeneous fluid subjected to large strain rates upon rapid, supercritical expansion in vacuum. Under picosecond irradiation, homogeneous and, at later times, heterogeneous melting of the superheated solid are followed by nonisochoric heating of the molten metal. In this case, the subcritical liquid material is subsequently cooled onto the binodal by thermal conduction and explosive boiling does not take place; as a result, ablation is associated with a “trivial” fragmentation process, i.e., the relatively slow expansion and dissociation into liquid droplets of supercritical matter near thermodynamic equilibrium. This implies a liquid-vapor equilibration time of ?10?11–10?10s and heating along the binodal under nanosecond irradiation. Solidification of the nonablated, supercooled molten material is eventually observed on a ?10?11–10?9s time scale, irrespective of the pulse duration.

Patrick Lorazo; Laurent J. Lewis; Michel Meunier

2006-04-14T23:59:59.000Z

382

Laser Cosmology  

E-Print Network [OSTI]

Recent years have seen tremendous progress in our understanding of the cosmos, which in turn points to even deeper questions to be further addressed. Concurrently the laser technology has undergone dramatic revolutions, providing exciting opportunity for science applications. History has shown that the symbiosis between direct observations and laboratory investigation is instrumental in the progress of astrophysics. We believe that this remains true in cosmology. Current frontier phenomena related to particle astrophysics and cosmology typically involve one or more of the following conditions: (1) extremely high energy events; (2) very high density, high temperature processes; (3) super strong field environments. Laboratory experiments using high intensity lasers can calibrate astrophysical observations, investigate underlying dynamics of astrophysical phenomena, and probe fundamental physics in extreme limits. In this article we give an overview of the exciting prospect of laser cosmology. In particular, we showcase its unique capability of investigating frontier cosmology issues such as cosmic accelerator and quantum gravity.

Pisin Chen

2014-02-24T23:59:59.000Z

383

Neutrino Spectroscopy with Atoms and Molecules  

E-Print Network [OSTI]

We give a comprehensive account of our proposed experimental method of using atoms or molecules in order to measure parameters of neutrinos still undetermined; the absolute mass scale, the mass hierarchy pattern (normal or inverted), the neutrino mass type (Majorana or Dirac), and the CP violating phases including Majorana phases. There are advantages of atomic targets, due to the closeness of available atomic energies to anticipated neutrino masses, over nuclear target experiments. Disadvantage of using atomic targets, the smallness of rates, is overcome by the macro-coherent amplification mechanism. The atomic or molecular process we use is a cooperative deexcitation of a collective body of atoms in a metastable level |e> emitting a neutrino pair and a photon; |e> -> |g> + gamma + nu_i nu_j where nu_i's are neutrino mass eigenstates. The macro-coherence is developed by trigger laser irradiation. We discuss aspects of the macro-coherence development by setting up the master equation for the target quantum state and propagating electric field. With a choice of heavy target atom or molecule such as Xe or I_2 that has a large M1 x E1 matrix element between |e> and |g>, we show that one can determine three neutrino masses along with the mass hierarchy pattern by measuring the photon spectral shape. If one uses a target of available energy of a fraction of 1 eV, Majorana CP phases may be determined. Our master equation, when applied to E1 x E1 transition such as pH_2 vibrational transition Xv=1 -> 0, can describe explosive PSR events in which most of the energy stored in |e> is released within a few nanoseconds. The present paper is intended to be self-contained explaining some details related theoretical works in the past, and further reports new simulations and our ongoing experimental efforts of the project to realize the neutrino mass spectroscopy using atoms/molecules.

Atsushi Fukumi; Susumu Kuma; Yuki Miyamoto; Kyo Nakajima; Itsuo Nakano; Hajime Nanjo; Chiaki Ohae; Noboru Sasao; Minoru Tanaka; Takashi Taniguchi; Satoshi Uetake; Tomonari Wakabayashi; Takuya Yamaguchi; Akihiro Yoshimi; Motohiko Yoshimura

2012-11-21T23:59:59.000Z

384

Output power characteristics of the neutral xenon long laser  

SciTech Connect (OSTI)

Lasers which oscillate within inhomogeneously broadened gain media exhibit spectral hole burning and concomitant reduction in output power compared with equivalent homogeneously-broadened laser gain media. By increasing the cavity length, it may be possible to demonstrate at least a partial transition from an inhomogeneous laser cavity mode spectrum to a homogeneous spectrum. There are a number of high gain laser lines which are inhomogeneously-broadened transitions in electric discharges of neutral xenon. In neutral xenon lasers, as in the cases of many other gas lasers, the inhomogeneous spectral broadening mechanism arises from Doppler shifts, {Delta}{nu}{sub D}, of individual atoms in thermal motion within the electric discharge comprising the laser gain medium. Optical transitions corresponding to these noble gas atoms have natural linewidths, {Delta}{nu}{sub n}{lt}{Delta}{nu}{sub D}. Simulations of the output power characteristics of the xenon laser were carried out as a function of laser cavity parameters, including the cavity length, L. These calculations showed that when the intracavity mode spacing frequency, c/2L{lt}{Delta}{nu}{sub n}, the inhomogeneously broadened xenon mode spectrum converted to a homogeneously broadened oscillation spectrum with an increase in output power. These simulations are compared with experimental results obtained for the long laser oscillation characteristics of the (5d[5/2]{degree}{sub 2}{r_arrow}6p[3/2]{sub 1}) transition corresponding to the strong, high-gain 3.508 {mu} line in xenon.

Linford, G.J. [TRW Space and Electronics Group, Redondo Beach, CA (United States). Space and Technology Div.

1994-12-31T23:59:59.000Z

385

In situ nitrogen-doped graphene grown from polydimethylsiloxane by plasma enhanced chemical vapor deposition  

SciTech Connect (OSTI)

Due to its unique electronic properties and wide spectrum of promising applications, graphene has attracted much attention from scientists in various fields. Control and engineering of graphene’s semiconducting properties is considered to be the key of its applications in electronic devices. Here, we report a novel method to prepare in situ nitrogen-doped graphene by microwave plasma assisted chemical vapor deposition (CVD) using PDMS (Polydimethylsiloxane) as a solid carbon source. Based on this approach, the concentration of nitrogen-doping can be easily controlled via the flow rate of nitrogen during the CVD process. X-ray photoelectron spectroscopy results indicated that the nitrogen atoms doped into graphene lattice were mainly in the forms of pyridinic and pyrrolic structures. Moreover, first-principles calculations show that the incorporated nitrogen atoms can lead to p-type doping of graphene. This in situ approach provides a promising strategy to prepare graphene with controlled electronic properties.

Wang, Chundong; Zhou, Yungang; He, Lifang; Ng, Tsz-Wai; Hong, Guo; Wu, Qi-Hui; Gao, Fei; Lee, Chun-Sing; Zhang, Wenjun

2013-01-21T23:59:59.000Z

386

Light storage via coherent population oscillation in a thermal cesium vapor  

E-Print Network [OSTI]

We report on the storage of light via the phenomenon of Coherent Population Oscillation (CPO) in an atomic cesium vapor at room temperature. In the experiment the optical information of a probe field is stored in the CPO of two ground states of a Lambda three-level system formed by the Zeeman sublevels of the hyperfine transition F = 3 - F' = 2 of cesium D2 line. We show directly that this CPO based memory is very insensitive to stray magnetic field inhomogeneities and presents a lifetime which is mainly limited only by atomic motion. A theoretical simulation of the measured spectra was also developed and is in very good agreement with the experiment.

A. J. F. de Almeida; J. Sales; M. -A. Maynard; T. Laupretre; F. Bretenaker; D. Felinto; F. Goldfarb; J. W. R. Tabosa

2014-09-19T23:59:59.000Z

387

Vapor-transport growth of high optical quality WSe{sub 2} monolayers  

SciTech Connect (OSTI)

Monolayer transition metal dichalcogenides are atomically thin direct-gap semiconductors that show a variety of novel electronic and optical properties with an optically accessible valley degree of freedom. While they are ideal materials for developing optical-driven valleytronics, the restrictions of exfoliated samples have limited exploration of their potential. Here, we present a physical vapor transport growth method for triangular WSe{sub 2} sheets of up to 30 ?m in edge length on insulating SiO{sub 2} substrates. Characterization using atomic force microscopy and optical microscopy reveals that they are uniform, monolayer crystals. Low temperature photoluminescence shows well resolved and electrically tunable excitonic features similar to those in exfoliated samples, with substantial valley polarization and valley coherence. The monolayers grown using this method are therefore of high enough optical quality for routine use in the investigation of optoelectronics and valleytronics.

Clark, Genevieve [Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195 (United States); Wu, Sanfeng; Rivera, Pasqual; Finney, Joseph; Nguyen, Paul; Cobden, David H. [Department of Physics, University of Washington, Seattle, Washington 98195 (United States); Xu, Xiaodong, E-mail: xuxd@uw.edu [Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195 (United States); Department of Physics, University of Washington, Seattle, Washington 98195 (United States)

2014-10-01T23:59:59.000Z

388

Ultraviolet versus infrared: Effects of ablation laser wavelength on the expansion of laser-induced plasma into one-atmosphere argon gas  

SciTech Connect (OSTI)

Laser-induced plasma from an aluminum target in one-atmosphere argon background has been investigated with ablation using nanosecond ultraviolet (UV: 355 nm) or infrared (IR: 1064 nm) laser pulses. Time- and space-resolved emission spectroscopy was used as a diagnostics tool to have access to the plasma parameters during its propagation into the background, such as optical emission intensity, electron density, and temperature. The specific feature of nanosecond laser ablation is that the pulse duration is significantly longer than the initiation time of the plasma. Laser-supported absorption wave due to post-ablation absorption of the laser radiation by the vapor plume and the shocked background gas plays a dominant role in the propagation and subsequently the behavior of the plasma. We demonstrate that the difference in absorption rate between UV and IR radiations leads to different propagation behaviors of the plasma produced with these radiations. The consequence is that higher electron density and temperature are observed for UV ablation. While for IR ablation, the plasma is found with lower electron density and temperature in a larger and more homogenous axial profile. The difference is also that for UV ablation, the background gas is principally evacuated by the expansion of the vapor plume as predicted by the standard piston model. While for IR ablation, the background gas is effectively mixed to the ejected vapor at least hundreds of nanoseconds after the initiation of the plasma. Our observations suggest a description by laser-supported combustion wave for the propagation of the plasma produced by UV laser, while that by laser-supported detonation wave for the propagation of the plasma produced by IR laser. Finally, practical consequences of specific expansion behavior for UV or IR ablation are discussed in terms of analytical performance promised by corresponding plasmas for application with laser-induced breakdown spectroscopy.

Ma Qianli; Motto-Ros, Vincent; Laye, Fabrice; Yu Jin [Universite de Lyon, F-69622, Lyon, France, Universite Lyon 1, Villeurbanne, CNRS, UMR5579, LASIM (France); Lei Wenqi; Bai Xueshi; Zheng Lijuan; Zeng Heping [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai (China)

2012-03-01T23:59:59.000Z

389

Laser ablated hard coating for microtools  

DOE Patents [OSTI]

Wear-resistant coatings composed of laser ablated hard carbon films, are deposited by pulsed laser ablation using visible light, on instruments such as microscope tips and micro-surgical tools. Hard carbon, known as diamond-like carbon (DLC), films produced by pulsed laser ablation using visible light enhances the abrasion resistance, wear characteristics, and lifetimes of small tools or instruments, such as small, sharp silicon tips used in atomic probe microscopy without significantly affecting the sharpness or size of these devices. For example, a 10--20 nm layer of diamond-like carbon on a standard silicon atomic force microscope (AFM) tip, enables the useful operating life of the tip to be increased by at least twofold. Moreover, the low inherent friction coefficient of the DLC coating leads to higher resolution for AFM tips operating in the contact mode. 12 figs.

McLean, W. II; Balooch, M.; Siekhaus, W.J.

1998-05-05T23:59:59.000Z

390

Laser ablated hard coating for microtools  

DOE Patents [OSTI]

Wear-resistant coatings composed of laser ablated hard carbon films, are deposited by pulsed laser ablation using visible light, on instruments such as microscope tips and micro-surgical tools. Hard carbon, known as diamond-like carbon (DLC), films produced by pulsed laser ablation using visible light enhances the abrasion resistance, wear characteristics, and lifetimes of small tools or instruments, such as small, sharp silicon tips used in atomic probe microscopy without significantly affecting the sharpness or size of these devices. For example, a 10-20 nm layer of diamond-like carbon on a standard silicon atomic force microscope (AFM) tip, enables the useful operating life of the tip to be increased by at least twofold. Moreover, the low inherent friction coefficient of the DLC coating leads to higher resolution for AFM tips operating in the contact mode.

McLean, II, William (Oakland, CA); Balooch, Mehdi (Berkeley, CA); Siekhaus, Wigbert J. (Berkeley, CA)

1998-05-05T23:59:59.000Z

391

New Combined Laser Ablation Platform Determines Cell Wall Chemistry (Fact Sheet)  

SciTech Connect (OSTI)

NREL has designed and developed a combined laser ablation/pulsed sample introduction/mass spectrometry platform that integrates pyrolysis and/or laser ablation with resonance-enhanced multiphoton ionization (REMPI) time-of-flight mass spectrometry. Using this apparatus, we can measure the cell wall chemical composition of untreated biomass materials. Understanding the chemical composition of untreated biomass is key to both the biochemical and thermochemical conversion of lignocellulosic biomass to biofuels. In the biochemical conversion process, the new technique provides a better understanding of the chemistry of lignin and will improve accessibility to plant sugars. In thermochemical conversion, the information provided by the new technique may help to reduce the formation of unwanted byproducts during gasification. NREL validated the ability of the system to detect pyrolysis products from plant materials using poplar, a potentially high-impact bioenergy feedstock. In the technique, biomass vapors are produced by laser ablation using the 3rd harmonic of an Nd:YAG laser (355 nm). The resulting vapors are entrained in a free jet expansion of helium, then skimmed and introduced into an ionization region. REMPI is used to ionize the vapors because it is highly sensitive for detecting lignin and aromatic metabolites. The laser ablation method was used to selectively volatilize specific plant tissues and detect lignin-based products from the vapors with enhanced sensitivity. This will allow the determination of lignin distribution in future biomass studies.

Not Available

2011-09-01T23:59:59.000Z

392

Atomic Energy Commission : Atomic Power at Shippingport - 1958 Educational Film  

SciTech Connect (OSTI)

The United States Atomic Energy Commission & Westinghouse Electric Company take us on a tour of an atomic power station.

None

2013-02-02T23:59:59.000Z

393

Coherence theory of the ring laser  

Science Journals Connector (OSTI)

Expressions for the fluctuations and correlations of the light emitted by a ring laser with counter-rotating traveling wave modes are derived theoretically. It is shown that the competition of the two modes for the excited atomic population leads to negative correlations between their intensity fluctuations, whose magnitude depends on the detuning of the laser cavity from the atomic line center. As a result of the mode competition, the relative intensity fluctuations do not die out in general as the working point of the laser is raised above threshold at line center, and the emitted light does not become fully coherent as in a conventional laser. The two-time amplitude and intensity correlation functions of the light are calculated at line center, and are shown to be expressible in terms of the eigenfunctions and eigenvalues of a certain Schrödinger equation, in complete analogy with the theory of the single-mode laser. However, the intensity correlation time increases with pump parameter above threshold, unlike that for the single-mode laser.

M. M- Tehrani and L. Mandel

1978-02-01T23:59:59.000Z

394

[TO APPEAR IN LASER PHYSICS] Quantum interference and its potential applications in a spectral hole-burning solid  

E-Print Network [OSTI]

above have been done with atomic beams or vapors. The diffusion of atoms in gas media, however this disadvantage, spectral hole-burning solids are a natural choice because of the absence of diffusion- and cascade-schemes.18 Efficient EIT in an optically solid material was first observed in a rare-earth crystal

Shahriar, Selim

395

Generalized Collective States and Their Role in a Collective State Atomic Interferometer and Atomic Clock  

E-Print Network [OSTI]

We investigate the behavior of an ensemble of N non-interacting, identical atoms, excited by a laser with a wavelength of $\\lambda$. In general, the i-th atom sees a Rabi frequency $\\Omega_i$, an initial position dependent laser phase $\\phi_i$, and a motion induced Doppler shift of $\\delta_i$. When $\\Omega_i=\\Omega$ and $\\delta_i=\\delta$ for all atoms, the system evolves into a superposition of (N+1) symmetric collective states (SCS), independent of the values of $\\phi_i$. If $\\phi_i=\\phi$ for all atoms, these states simplify to the well-known Dicke collective states. When $\\Omega_i$ or $\\delta_i$ is distinct for each atom, the system evolves into a superposition of SCS as well as asymmetric collective states (ACS). For large N, the number of ACS's $(2^N-N-1)$ is far greater than that of the SCS. We show how to formulate the properties of all the collective states under various non-idealities, and use this formulation to understand the dynamics thereof. For the case where $\\Omega_i=\\Omega$ and $\\delta_i=\\delta$ for all atoms, we show how to determine the amplitudes of the generalized collective states in a simple manner. For the case where $\\Omega_i$ or $\\delta_i$ is distinct for each atom, we show how the SCS and ACS's can be treated on the same footing. Furthermore, we show that the collective states corresponding to the absorption of a given number of photons can be visualized as an abstract, multi-dimensional rotation in the Hilbert space spanned by the ordered product states of individual atoms. We also consider the effect of treating the center of mass degree of freedom of the atoms quantum mechanically on the description of the collective states. Specifically, we show that it is indeed possible to construct a generalized collective state, as needed for the collective state atomic interferometer we recently proposed, when each atom is assumed to be in a localized wave packet.

Resham Sarkar; May E. Kim; Renpeng Fang; Yanfei Tu; Selim M. Shahriar

2014-08-11T23:59:59.000Z

396

Chemiluminescence in the Reaction of Mn Atoms with CF4  

Science Journals Connector (OSTI)

Translational excitation functions have been determined for production of several MnF* statesb5?, c5?+, d5?, and (most probably) e5?+in the reaction of a laser-ablated beam of Mn atoms with gaseous CF4. Although all observed channels show high initial ...

Dale L. Herbertson; Martin R. Levy

1996-08-29T23:59:59.000Z

397

An Atomic Gravitational Wave Interferometric Sensor (AGIS)  

SciTech Connect (OSTI)

We propose two distinct atom interferometer gravitational wave detectors, one terrestrial and another satellite-based, utilizing the core technology of the Stanford 10m atom interferometer presently under construction. Each configuration compares two widely separated atom interferometers run using common lasers. The signal scales with the distance between the interferometers, which can be large since only the light travels over this distance, not the atoms. The terrestrial experiment with baseline {approx} 1 km can operate with strain sensitivity {approx} 10{sup -19}/{radical}Hz in the 1 Hz-10 Hz band, inaccessible to LIGO, and can detect gravitational waves from solar mass binaries out to megaparsec distances. The satellite experiment with baseline {approx} 1000 km can probe the same frequency spectrum as LISA with comparable strain sensitivity {approx} 10{sup -20}/{radical}Hz. The use of ballistic atoms (instead of mirrors) as inertial test masses improves systematics coming from vibrations, acceleration noise, and significantly reduces spacecraft control requirements. We analyze the backgrounds in this configuration and discuss methods for controlling them to the required levels.

Dimopoulos, Savas; /Stanford U., Phys. Dept.; Graham, Peter W.; /SLAC; Hogan, Jason M.; Kasevich, Mark A.; /Stanford U., Phys. Dept.; Rajendran, Surjeet; /SLAC /Stanford U., Phys. Dept.

2008-08-01T23:59:59.000Z

398

Phase diagram for injection locking a superradiant laser  

E-Print Network [OSTI]

We experimentally and theoretically study the response of a superradiant or bad-cavity laser to an applied coherent drive. We observe two forms of synchronization (injection locking) between the superradiant ensemble and the applied drive: one attractive and one repulsive in nature. We explain the region of repulsion as arising from the higher three-dimensional description of the atomic spin state that stores the laser coherence in a superradiant laser, as opposed to a two-parameter description of the electric field in a traditional good-cavity laser. We derive a phase diagram of predicted behavior and experimentally measure the response of the system across various trajectories therein.

Kevin C. Cox; Joshua M. Weiner; James K. Thompson

2014-06-19T23:59:59.000Z

399

ARM - Field Campaign - Fall 1997 Water Vapor IOP  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Water Vapor IOP Water Vapor IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Fall 1997 Water Vapor IOP 1997.09.15 - 1997.10.05 Lead Scientist : Henry Revercomb For data sets, see below. Summary The Water Vapor IOP was conducted as a follow-up to a predecessor IOP on water vapor held in September 1996. This IOP relied heavily on both ground-based guest and CART instrumentation and in-situ aircraft and tethered sonde/kite measurements. Primary operational hours were from 6 p.m. Central until at least midnight, with aircraft support normally from about 9 p.m. until midnight when available. However, many daytime measurements were made to support this IOP. The first Water Vapor IOP primarily concentrated on the atmosphere's lowest

400

G-Band Vapor Radiometer Profiler (GVRP) Handbook  

SciTech Connect (OSTI)

The G-Band Vapor Radiometer Profiler (GVRP) provides time-series measurements of brightness temperatures from 15 channels between 170 and 183.310 GHz. Atmospheric emission in this spectral region is primarily due to water vapor, with some influence from liquid water. Channels between 170.0 and 176.0 GHz are particularly sensitive to the presence of liquid water. The sensitivity to water vapor of the 183.31-GHz line is approximately 30 times higher than at the frequencies of the two-channel microwave radiometer (MWR) for a precipitable water vapor (PWV) amount of less than 2.5 mm. Measurements from the GVRP instrument are therefore especially useful during low-humidity conditions (PWV < 5 mm). In addition to integrated water vapor and liquid water, the GVRP can provide low-resolution vertical profiles of water vapor in very dry conditions.

Caddeau, MP

2010-06-23T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Light narrowing of magnetic resonance lines in dense, optically pumped alkali-metal vapor  

Science Journals Connector (OSTI)

A new and unusual phenomenon which we call light narrowing is reported and discussed in this paper. We discovered this effect in dense, spin-polarized cesium vapor optically pumped with a cw blue dye laser beam tuned to the second resonance D1 line (4593 Å). We observe a significant narrowing of the radio-frequency power-broadened magnetic resonance lines (linewidths narrow by as much as a factor of 2.5) when the intensity of the circularly polarized incident dye laser beam is increased by either focusing the beam or by the removal of attenuating filters from the focused beam. The magnetic resonance linewidths in spin-polarized cesium vapor were measured over a wide range of cesium number densities (5×1012 cm-3 ?[Cs]?1×1016 cm-3). This corresponds to cesium spinexchange rates of 4.5×103 to 9×106 sec-1. For low cesium number densities (5×1012 1×1015 cm-3) this light-narrowing effect almost completely disappears. In the limit of low-radio-frequency power the magnetic resonance linewidths for focused and unfocused dye laser beam are nearly the same. Experimental observations on this new effect are presented in detail. In the latter part of this paper a self-contained theoretical treatment of the light-narrowing effect is developed. Using Bloch equations in the presence of optical pumping, spin relaxation (diffusion, electron randomization), rapid spin exchange, and radio-frequency magnetic field, expressions for magnetic resonance line shapes are derived. In general, we find good agreement between our experimental results and the theory.

N. D. Bhaskar; J. Camparo; W. Happer; A. Sharma

1981-06-01T23:59:59.000Z

402

Vapor port and groundwater sampling well  

DOE Patents [OSTI]

A method and apparatus has been developed for combining groundwater monitoring wells with unsaturated-zone vapor sampling ports. The apparatus allows concurrent monitoring of both the unsaturated and the saturated zone from the same well at contaminated areas. The innovative well design allows for concurrent sampling of groundwater and volatile organic compounds (VOCs) in the vadose (unsaturated) zone from a single well, saving considerable time and money. The sample tubes are banded to the outer well casing during installation of the well casing.

Hubbell, Joel M. (Idaho Falls, ID); Wylie, Allan H. (Idaho Falls, ID)

1996-01-01T23:59:59.000Z

403

Chemical vapor deposition of epitaxial silicon  

DOE Patents [OSTI]

A single chamber continuous chemical vapor deposition (CVD) reactor is described for depositing continuously on flat substrates, for example, epitaxial layers of semiconductor materials. The single chamber reactor is formed into three separate zones by baffles or tubes carrying chemical source material and a carrier gas in one gas stream and hydrogen gas in the other stream without interaction while the wafers are heated to deposition temperature. Diffusion of the two gas streams on heated wafers effects the epitaxial deposition in the intermediate zone and the wafers are cooled in the final zone by coolant gases. A CVD reactor for batch processing is also described embodying the deposition principles of the continuous reactor.

Berkman, Samuel (Florham Park, NJ)

1984-01-01T23:59:59.000Z

404

Recovery of benzene in an organic vapor monitor  

E-Print Network [OSTI]

solid adsorbents available (silica gel, activated alumina, etc. ), activated charcoal is most frequently utilized. Activated charcoal has retentivity for sorbed vapors several times that of silica gel and it displays a selectivity for organic vapors... (diffusion rate) of the vapor molecules to the sur- face of the adsorbent. The adsorption process determine how effective the adsorbent collects and holds the contam- inant on the surface of the activated charcoal. Recovery of the contaminant from...

Krenek, Gregory Joel

2012-06-07T23:59:59.000Z

405

Design of a dual species atom interferometer for space  

E-Print Network [OSTI]

Atom interferometers have a multitude of proposed applications in space including precise measurements of the Earth's gravitational field, in navigation & ranging, and in fundamental physics such as tests of the weak equivalence principle (WEP) and gravitational wave detection. While atom interferometers are realized routinely in ground-based laboratories, current efforts aim at the development of a space compatible design optimized with respect to dimensions, weight, power consumption, mechanical robustness and radiation hardness. In this paper, we present a design of a high-sensitivity differential dual species $^{85}$Rb/$^{87}$Rb atom interferometer for space, including physics package, laser system, electronics and software. The physics package comprises the atom source consisting of dispensers and a 2D magneto-optical trap (MOT), the science chamber with a 3D-MOT, a magnetic trap based on an atom chip and an optical dipole trap (ODT) used for Bose-Einstein condensate (BEC) creation and interferometry...

Schuldt, Thilo; Krutzik, Markus; Bote, Lluis Gesa; Gaaloul, Naceur; Hartwig, Jonas; Ahlers, Holger; Herr, Waldemar; Posso-Trujillo, Katerine; Rudolph, Jan; Seidel, Stephan; Wendrich, Thijs; Ertmer, Wolfgang; Herrmann, Sven; Kubelka-Lange, André; Milke, Alexander; Rievers, Benny; Rocco, Emanuele; Hinton, Andrew; Bongs, Kai; Oswald, Markus; Franz, Matthias; Hauth, Matthias; Peters, Achim; Bawamia, Ahmad; Wicht, Andreas; Battelier, Baptiste; Bertoldi, Andrea; Bouyer, Philippe; Landragin, Arnaud; Massonnet, Didier; Lévèque, Thomas; Wenzlawski, Andre; Hellmig, Ortwin; Windpassinger, Patrick; Sengstock, Klaus; von Klitzing, Wolf; Chaloner, Chris; Summers, David; Ireland, Philip; Mateos, Ignacio; Sopuerta, Carlos F; Sorrentino, Fiodor; Tino, Guglielmo M; Williams, Michael; Trenkel, Christian; Gerardi, Domenico; Chwalla, Michael; Burkhardt, Johannes; Johann, Ulrich; Heske, Astrid; Wille, Eric; Gehler, Martin; Cacciapuoti, Luigi; Gürlebeck, Norman; Braxmaier, Claus; Rasel, Ernst

2014-01-01T23:59:59.000Z

406

Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) | Open Energy  

Open Energy Info (EERE)

Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Haleakala Volcano Area (Thomas, 1986) Exploration Activity Details Location Haleakala Volcano Area Exploration Technique Mercury Vapor Activity Date Usefulness not indicated DOE-funding Unknown Notes The field survey program on the northwest rift zone consisted of soil mercury and radon emanometry surveys, groundwater temperature and chemistry studies, Schlumberger resistivity soundings and self-potential profiles. Geophysical and geochemical surveys along this rift (southwest) were limited by difficult field conditions and access limitations. The geophysical program consisted of one Schlumberger sounding, one

407

Mercury Vapor At Vale Hot Springs Area (Varekamp & Buseck, 1983...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Vale Hot Springs Area (Varekamp & Buseck, 1983) Exploration Activity Details...

408

Mercury Vapor At Breitenbush Hot Springs Area (Varekamp & Buseck...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Breitenbush Hot Springs Area (Varekamp & Buseck, 1983) Exploration Activity...

409

Mercury Vapor At Mickey Hot Springs Area (Varekamp & Buseck,...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Mickey Hot Springs Area (Varekamp & Buseck, 1983) Exploration Activity...

410

Mercury Vapor At Desert Peak Area (Varekamp & Buseck, 1983) ...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Desert Peak Area (Varekamp & Buseck, 1983) Exploration Activity Details...

411

Mercury Vapor At Socorro Mountain Area (Kooten, 1987) | Open...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Socorro Mountain Area (Kooten, 1987) Exploration Activity Details Location...

412

Mercury Vapor At Lassen Volcanic National Park Area (Varekamp...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Lassen Volcanic National Park Area (Varekamp & Buseck, 1983) Exploration...

413

Thermal Performance of a Double-Tube Type Lng Vaporizer  

Science Journals Connector (OSTI)

This report concerns the confirmed test results and method of analysis of the thermal performance of a double-tube type LNG vaporizer (DTV). The DTV is a...

Y. Miyata; T. Miura; S. Kasahara; H. Shohtani…

1994-01-01T23:59:59.000Z

414

Optimal Control of Vapor Extraction of Heavy Oil.  

E-Print Network [OSTI]

??Vapor extraction (Vapex) process is an emerging technology for viscous oil recovery that has gained much attention in the oil industry. However, the oil production… (more)

Muhamad, Hameed (Author)

2012-01-01T23:59:59.000Z

415

Geographic Information System At Cove Fort Area - Vapor (Nash...  

Open Energy Info (EERE)

navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geographic Information System At Cove Fort Area - Vapor (Nash, Et Al., 2002) Exploration Activity Details...

416

Raman Lidar Measurements of Aerosols and Water Vapor During the...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

modifications reduced but could not eliminate these adverse effects. The Raman lidar water vapor (aerosol extinction) measurements produced by these modified algorithms were,...

417

Thermal Gradient Holes At Cove Fort Area - Vapor (Warpinski,...  

Open Energy Info (EERE)

Warpinski, Et Al., 2004) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermal Gradient Holes At Cove Fort Area - Vapor (Warpinski, Et Al.,...

418

Ground Magnetics At Cove Fort Area - Vapor (Warpinski, Et Al...  

Open Energy Info (EERE)

Vapor (Warpinski, Et Al., 2004) Exploration Activity Details Location Cove Fort Geothermal Area Exploration Technique Ground Magnetics Activity Date Usefulness useful DOE-funding...

419

Laser stabilization using spectral hole burning  

E-Print Network [OSTI]

We have frequency stabilized a Coherent CR699-21 dye laser to a transient spectral hole on the 606 nm transition in Pr^{+3}:Y_2SiO_5. A frequency stability of 1 kHz has been obtained on the 10 microsecond timescale together with a long-term frequency drift below 1 kHz/s. RF magnetic fields are used to repopulate the hyperfine levels allowing us to control the dynamics of the spectral hole. A detailed theory of the atomic response to laser frequency errors has been developed which allows us to design and optimize the laser stabilization feedback loop, and specifically we give a stability criterion that must be fulfilled in order to obtain very low drift rates. The laser stability is sufficient for performing quantum gate experiments in Pr^{+3}:Y_2SiO_5.

L. Rippe; B. Julsgaard; A. Walther; S. Kröll

2006-11-05T23:59:59.000Z

420

Gas lasers with wave-chaotic resonators  

E-Print Network [OSTI]

Semiclassical multimode laser theory is extended to gas lasers with open two-dimensional resonators of arbitrary shape. The Doppler frequency shift of the linear-gain coefficient leads to an additional linear coupling between the modes, which, however, is shown to be negligible. The nonlinear laser equations simplify in the special case of wave-chaotic resonators. In the single-mode regime, the intensity of a chaotic laser, as a function of the mode frequency, displays a local minimum at the frequency of the atomic transition. The width of the minimum scales with the inhomogeneous linewidth, in contrast to the Lamb dip in uniaxial resonators whose width is given by the homogeneous linewidth.

Oleg Zaitsev

2010-10-28T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Practical scheme for a light-induced gauge field in an atomic Bose gas  

Science Journals Connector (OSTI)

We propose a scheme to generate an Abelian gauge field in an atomic gas using two crossed laser beams. If the internal atomic state follows adiabatically the eigenstates of the atom-laser interaction, Berry’s phase gives rise to a vector potential that can nucleate vortices in a Bose gas. The present scheme operates even for a large detuning with respect to the atomic resonance, making it applicable to alkali-metal atoms without significant heating due to spontaneous emission. We test the validity of the adiabatic approximation by integrating the set of coupled Gross-Pitaevskii equations associated with the various internal atomic states, and we show that the steady state of the interacting gas indeed exhibits a vortex lattice, as expected from the adiabatic gauge field.

Kenneth J. Günter, Marc Cheneau, Tarik Yefsah, Steffen P. Rath, and Jean Dalibard

2009-01-21T23:59:59.000Z

422

ATOMS PEACE WAR Eisenhower  

Broader source: Energy.gov (indexed) [DOE]

ATOMS ATOMS PEACE WAR Eisenhower and the Atomic Energy Commission Richard G. Hewlett and lack M. Roll With a Foreword by Richard S. Kirkendall and an Essay on Sources by Roger M. Anders University of California Press Berkeley Los Angeles London Published 1989 by the University of California Press Berkeley and Los Angeles, California University of California Press, Ltd. London, England Prepared by the Atomic Energy Commission; work made for hire. Library of Congress Cataloging-in-Publication Data Hewlett, Richard G. Atoms for peace and war, 1953-1961. (California studies in the history of science) Bibliography: p. Includes index. 1. Nuclear energy-United States-History. 2. U.S. Atomic Energy Commission-History. 3. Eisenhower, Dwight D. (Dwight David), 1890-1969.

423

Ultrafast laser based coherent control methods for explosives detection  

SciTech Connect (OSTI)

The detection of explosives is a notoriously difficult problem, especially at stand-off, due to their (generally) low vapor pressure, environmental and matrix interferences, and packaging. We are exploring Optimal Dynamic Detection of Explosives (ODD-Ex), which exploits the best capabilities of recent advances in laser technology and recent discoveries in optimal shaping of laser pulses for control of molecular processes to significantly enhance the standoff detection of explosives. The core of the ODD-Ex technique is the introduction of optimally shaped laser pulses to simultaneously enhance sensitivity to explosives signatures while dramatically improving specificity, particularly against matrix materials and background interferences. These goals are being addressed by operating in an optimal non-linear fashion, typically with a single shaped laser pulse inherently containing within it coherently locked control and probe subpulses. Recent results will be presented.

Moore, David Steven [Los Alamos National Laboratory

2010-12-06T23:59:59.000Z

424

Method for changing the cross section of a laser beam  

DOE Patents [OSTI]

A technique is disclosed herein in which a circular optical beam, for example a copper vapor laser (CVL) beam, is converted to a beam having a profile other than circular, e.g. square or triangular. This is accomplished by utilizing a single optical mirror having a reflecting surface designed in accordance with a specifically derived formula in order to make the necessary transformation, without any substantial light loss and without changing substantially the intensity profile of the circular beam which has a substantially uniform intensity profile. In this way, the output beam can be readily directed into the dye cell of a dye laser. 4 figs.

Sweatt, W.C.; Seppala, L.

1995-12-05T23:59:59.000Z

425

Atomic Collapse Observed  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 | Tags: Hopper, Materials Science Contact: Linda...

426

Multiplicative Sets of Atoms.  

E-Print Network [OSTI]

??It is possible for an element to have both an atom factorization and a factorization that will always contain a reducible element. This leads us… (more)

Rand, Ashley Nicole

2013-01-01T23:59:59.000Z

427

Improved graphite furnace atomizer  

DOE Patents [OSTI]

A graphite furnace atomizer for use in graphite furnace atomic absorption spectroscopy is described wherein the heating elements are affixed near the optical path and away from the point of sample deposition, so that when the sample is volatilized the spectroscopic temperature at the optical path is at least that of the volatilization temperature, whereby analyteconcomitant complex formation is advantageously reduced. The atomizer may be elongated along its axis to increase the distance between the optical path and the sample deposition point. Also, the atomizer may be elongated along the axis of the optical path, whereby its analytical sensitivity is greatly increased.

Siemer, D.D.

1983-05-18T23:59:59.000Z

428

Atom Nano-Optics  

Science Journals Connector (OSTI)

Nanolocalized light fields composed of photon dots and photon holes are being used to control the motion of atoms on a nanometer spatial scale.

Balykin, Victor; Klimov, Vasilii; Letokhov, Vladilen

2005-01-01T23:59:59.000Z

429

Cutting and drilling studies using high power visible lasers  

SciTech Connect (OSTI)

High power and radiance laser technologies developed at Lawrence Livermore National Laboratory such as copper-vapor and dye lasers show great promise for material processing tasks. Evaluation of models suggests significant increases in welding, cutting, and drilling capabilities, as well as applications in emerging technologies such as micromachining, surface treatment, and stereolithography. Copper lasers currently operate at 1.8 kW output at approximately three times the diffraction limit and achieve mean time between failures of more than 1,000 hours. Dye lasers have near diffraction limited beam quality at greater than 1.0 kW. Results from cutting and drilling studies in titanium and stainless steel alloys show that cuts and holes with extremely fine features can be made with dye and copper-vapor lasers. High radiance beams produce low distortion and small heat-affected zones. The authors have accomplished very high aspect ratios (> 60:1) and features with micron scale (5-50 {mu}m) sizes. The paper gives a description of the equipment; discusses cutting theory; and gives experimental results of cutting and drilling studies on Ti-6Al-4V and 304 stainless steel.

Kautz, D.D.; Dragon, E.P.; Werve, M.E.; Hargrove, R.S.; Warner, B.E.

1993-05-27T23:59:59.000Z

430

Broadening of the spectral lines of a buffer gas and target substance in laser ablation  

SciTech Connect (OSTI)

The broadening of discrete spectral lines from the plasma produced in the laser ablation of metal targets in a broad pressure range (10{sup 2} - 10{sup 7} Pa) of the ambient gas (Ar, He, H{sub 2}) was studied experimentally. The behaviour of spectral line broadening for the buffer gases was found to be significantly different from that for the atoms and ions of the target material. In comparison with target atoms, the atoms of buffer gases radiate from denser plasma layers, and their spectral line profiles are complex in shape. (interaction of laser radiation with matter. laser plasma)

Kask, Nikolai E; Michurin, Sergei V [D.V. Skobel'tsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

2012-11-30T23:59:59.000Z

431

Control of physical properties on solid surface via laser processing  

SciTech Connect (OSTI)

In a safety operation of a nuclear power plant, vapor conditions such as a droplet or liquid membrane toward a solid surface of a heat exchanger and reactor vessel is important. In the present study, focusing on the droplet, the wettability on solid surface and surface free energy of solid are evaluated. In addition, wettability on a metal plate fabricated by laser processing is also considered for the nuclear engineering application.

Yonemoto, Yukihiro; Nishimura, Akihiko [Applied Laser Technology Institute, Japan Atomic Energy Agency, 65-20 Kizaki, Tsuruga, Fukui (Japan)

2012-07-11T23:59:59.000Z

432

Integration of Global Positioning System and Scanning Water Vapor Radiometers for Precipitable Water Vapor and Cloud Liquid Path Estimates  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Integration of Global Positioning System and Scanning Integration of Global Positioning System and Scanning Water Vapor Radiometers for Precipitable Water Vapor and Cloud Liquid Path Estimates V. Mattioli and P. Basili Department of Electronic and Information Engineering University of Perugia Perugia, Italy E. R. Westwater Cooperative Institute for Research in Environmental Sciences University of Colorado National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado Introduction In recent years the Global Positioning System (GPS) has proved to be a reliable instrument for measuring precipitable water vapor (PWV) (Bevis et al. 1992), offering an independent source of information on water vapor when compared with microwave radiometers (MWRs), and/or radiosonde

433

Vapor and gas sampling of Single-Shell Tank 241-T-111 using the vapor sampling system  

SciTech Connect (OSTI)

This document presents sampling data resulting from the January 20, 1995, sampling of SST 241-T-111 using the vapor sampling system.

Caprio, G.S.

1995-09-01T23:59:59.000Z

434

Vapor and gas sampling of single-shell tank 241-BY-112 using the vapor sampling system  

SciTech Connect (OSTI)

This document presents sampling data from the November 18, 1994, sampling of SST 241-BY-112 using the vapor sampling system.

Caprio, G.S.

1995-09-20T23:59:59.000Z

435

Development of nanodiamond foils for H- stripping to Support the Spallation Neutron Source (SNS) using hot filament chemical vapor deposition  

SciTech Connect (OSTI)

Thin diamond foils are needed in many particle accelerator experiments regarding nuclear and atomic physics, as well as in some interdisciplinary research. Particularly, nanodiamond texture is attractive for this purpose as it possesses a unique combination of diamond properties such as high thermal conductivity, mechanical strength and high radiation hardness; therefore, it is a potential material for energetic ion beam stripper foils. At the ORNL Spallation Neutron Source (SNS), the installed set of foils must be able to survive a nominal five-month operation period, without the need for unscheduled costly shutdowns and repairs. Thus, a small foil about the size of a postage stamp is critical to the operation of SNS and similar sources in U.S. laboratories and around the world. We are investigating nanocrystalline, polycrystalline and their admixture films fabricated using a hot filament chemical vapor deposition (HFCVD) system for H- stripping to support the SNS at Oak Ridge National Laboratory. Here we discuss optimization of process variables such as substrate temperature, process gas ratio of H2/Ar/CH4, substrate to filament distance, filament temperature, carburization conditions, and filament geometry to achieve high purity diamond foils on patterned silicon substrates with manageable intrinsic and thermal stresses so that they can be released as free standing foils without curling. An in situ laser reflectance interferometry tool (LRI) is used for monitoring the growth characteristics of the diamond thin film materials. The optimization process has yielded free standing foils with no pinholes. The sp3/sp2 bonds are controlled to optimize electrical resistivity to reduce the possibility of surface charging of the foils. The integrated LRI and HFCVD process provides real time information on the growth of films and can quickly illustrate growth features and control film thickness. The results are discussed in the light of development of nanodiamond foils that will be able to withstand a few MW proton beam and hopefully will be able to be used after possible future upgrades to the SNS to greater than a 3MW beam.

Vispute, R D [Blue Wave Semiconductors; Ermer, Henry K [Blue Wave Semiconductors; Sinsky, Phillip [Blue Wave Semiconductors; Seiser, Andrew [Blue Wave Semiconductors; Shaw, Robert W [ORNL; Wilson, Leslie L [ORNL

2014-01-01T23:59:59.000Z

436

Pulsed laser irradiation of metal multilayers.  

SciTech Connect (OSTI)

Vapor-deposited, exothermic metal-metal multilayer foils are an ideal class of materials for detailed investigations of pulsed laser-ignited chemical reactions. Created in a pristine vacuum environment by sputter deposition, these high purity materials have well-defined reactant layer thicknesses between 1 and 1000 nm, minimal void density and intimate contact between layers. Provided that layer thicknesses are made small, some reactive metal-metal multilayer foils can be ignited at a point by laser irradiation and exhibit subsequent high-temperature, self-propagating synthesis. With this presentation, we describe the pulsed laser-induced ignition characteristics of a single multilayer system (equiatomic Al/Pt) that exhibits self-propagating synthesis. We show that the thresholds for ignition are dependent on (i) multilayer design and (ii) laser pulse duration. With regard to multilayer design effects on ignition, there is a large range of multilayer periodicity over which ignition threshold decreases as layer thicknesses are made small. We attribute this trend of decreased ignition threshold to reduced mass transport diffusion lengths required for rapid exothermic mixing. With regard to pulse duration effects, we have determined how ignition threshold of a single Al/Pt multilayer varies with pulse duration from 10{sup -2} to {approx} 10{sup -13} sec (wavelength and spot size are held constant). A higher laser fluence is required for ignition when using a single laser pulse {approx} 100 fs or 1 ps compared with nanosecond or microsecond exposure, and we attribute this, in part, to the effects of reactive material being ablated when using the shorter pulse durations. To further understand these trends and other pulsed laser-based processes, our discussion concludes with an analysis of the heat-affected depths in multilayers as a function of pulse duration.

Adams, David Price; McDonald, Joel Patrick

2010-11-01T23:59:59.000Z

437

Nuclear Proliferation Using Laser Isotope Separation -- Verification Options  

SciTech Connect (OSTI)

Two levels of nonproliferation verification exist. Signatories of the basic agreements under the Nuclear Non-proliferation Treaty (NPT) agree to open their nuclear sites to inspection by the IAEA. A more detailed and intrusive level was developed following the determination that Iraq had begun a nuclear weapons development program that was not detected by the original level of verification methods. This level, referred to as 93+2 and detailed in model protocol INFCIRC/540, allows the IAEA to do environmental monitoring of non-declared facilities that are suspected of containing proliferation activity, and possibly further inspections, as well as allowing more detailed inspections of declared sites. 56 countries have signed a Strengthened Safeguards Systems Additional Protocol as of 16 July 2001. These additional inspections can be done on the instigation of the IAEA itself, or after requests by other parties to the NPT, based on information that they have collected. Since information able to cause suspicion of proliferation could arrive at any country, it is important that countries have procedures in place that will assist them in making decisions related to these inspections. Furthermore, IAEA inspection resources are limited, and therefore care needs to be taken to make best use of these resources. Most of the nonproliferation verification inspections may be concentrated on establishing that diversion of nuclear materials is not occurring, but some fraction will be related to determining if undeclared sites have nuclear materials production taking place within them. Of these, most suspicions will likely be related to the major existing technologies for uranium enrichment and reprocessing for plutonium extraction, as it would seem most likely that nations attempting proliferation would use tested means of producing nuclear materials. However, as technology continues to advance and new methods of enrichment and reprocessing are developed, inspection-related procedures will need to be adapted to keep up with them. In order to make 93+2 inspections more useful, a systematic way of finding clues to nuclear proliferation would be useful. Also, to cope with the possible use of newer technology for proliferation, the list of clues might need to be expanded. This paper discusses the development and recognition of such clues. It concentrates on laser isotope separation (LIS) as a new proliferation technology, and uses Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) as an example of LIS that is well known.

Erickson, S A

2001-10-15T23:59:59.000Z

438

Interacting double dark resonances in a hot atomic vapor of helium  

SciTech Connect (OSTI)

We experimentally and theoretically study two different tripod configurations using metastable helium ({sup 4}He*), with the probe field polarization perpendicular and parallel to the quantization axis, defined by an applied weak magnetic field. In the first case, the two dark resonances interact incoherently and merge together into a single electromagnetically induced transparency peak with increasing coupling power. In the second case, we observe destructive interference between the two dark resonances inducing an extra absorption peak at the line center.

Kumar, S.; Ghosh, R. [School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067 (India); Laupretre, T.; Bretenaker, F.; Goldfarb, F. [Laboratoire Aime Cotton, CNRS-Universite Paris Sud 11, F-91405 Orsay Cedex (France)

2011-08-15T23:59:59.000Z

439

Enhancement of field generation via maximal atomic coherence prepared by fast adiabatic passage in Rb vapor  

E-Print Network [OSTI]

shift s200 MHzd. The optical path lengths for both beams are the same. The temporal be- havior of the pulses is detected by fast photodiode D3. One beam serves as the first coupling pulse and the probe pulse. The time duration of the first coupling... with opposite circular polar- izations are separated by a second l /4 wave plate and an- other polarizing beamsplitter. The transmitted first coupling pulse and probe pulse are detected by fast photodiode D1. The second coupling pulse and the generated...

Sautenkov, V. A.; Ye, C. Y.; Rostovtsev, Y. V.; Welch, George R.; Scully, Marlan O.

2004-01-01T23:59:59.000Z

440

Wireless Network Control of Interacting Rydberg Atoms  

Science Journals Connector (OSTI)

We identify a relation between the dynamics of ultracold Rydberg gases in which atoms experience a strong dipole blockade and spontaneous emission, and a stochastic process that models certain wireless random-access networks. We then transfer insights and techniques initially developed for these wireless networks to the realm of Rydberg gases, and explain how the Rydberg gas can be driven into crystal formations using our understanding of wireless networks. Finally, we propose a method to determine Rabi frequencies (laser intensities) such that particles in the Rydberg gas are excited with specified target excitation probabilities, providing control over mixed-state populations.

Jaron Sanders; Rick van Bijnen; Edgar Vredenbregt; Servaas Kokkelmans

2014-04-22T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Laser trapping of short-lived radioactive isotopes  

Science Journals Connector (OSTI)

We describe an experiment which demonstrates the feasibility of trapping significant quantities of short-lived radioactive atoms with laser light. A thermal beam of 22.5 sec half-life Na21 atoms was produced on-line at the LBL 88’’ Cyclotron. After decelerating the beam using a Zeeman-tuned slowing technique we stored about 4×103 Na21 atoms in a magneto-optical trap. The number of trapped atoms is large enough to be used in experimental studies of the beta decay of Na21. The basic method can be adapted for other rare isotopes.

Z-T. Lu; C. Bowers; S. J. Freedman; B. K. Fujikawa; J. L. Mortara; S-Q. Shang; K. P. Coulter; L. Young

1994-06-13T23:59:59.000Z

442

Intracavity Sensing via Compliance Voltage in an External Cavity Quantum Cascade Laser  

SciTech Connect (OSTI)

We demonstrate a technique for gas phase spectroscopy and sensing by detecting changes in compliance voltage of an external cavity quantum cascade laser due to intracavity absorption. The technique is characterized and used to measure the absorption spectrum of water vapor and Freon-134a.

Phillips, Mark C.; Taubman, Matthew S.

2012-07-01T23:59:59.000Z

443

Jupiter Laser Facility  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Jupiter Laser Facility The commissioning of the Titan Petawatt-Class laser to LLNL's Jupiter Laser Facility (JLF) has provided a unique platform for the use of petawatt (PW)-class...

444

Hypersonic gasdynamic laser system  

SciTech Connect (OSTI)

This patent describes a visible, or near to mid infra-red, hypersonic gas dynamic laser system. It comprises: a hypersonic vehicle for carrying the hypersonic gas dynamic laser system, and also providing high energy ram air for thermodynamic excitation and supply of the laser gas; a laser cavity defined within the hypersonic vehicle and having a laser cavity inlet for the laser cavity formed by an opening in the hypersonic vehicle, such that ram air directed through the laser cavity opening supports gas dynamic lasing operations at wavelengths less than 10.6{mu} meters in the laser cavity; and an optical train for collecting the laser radiation from the laser cavity and directing it as a substantially collimated laser beam to an output aperture defined by an opening in the hypersonic vehicle to allow the laser beam to be directed against a target.

Foreman, K.M.; Maciulaitis, A.

1990-05-22T23:59:59.000Z

445

Terahertz quantum cascade lasers  

Science Journals Connector (OSTI)

...Michael Pepper Terahertz quantum cascade lasers Jerome Faist 1 Lassaad Ajili...developments in terahertz quantum cascade lasers are reviewed. Structures...magnetic confinement| Terahertz quantum cascade lasers. | Recent developments in...

2004-01-01T23:59:59.000Z

446

Atoms for Peace Awards  

Science Journals Connector (OSTI)

... Technology, is to be chairman of the Organization and Planning Committee of Atoms for Peace Awards. In addition to Dr. Killian, the Committee will include Dr. Detlev W. ... and Dr. Alan Waterman, director of the National Science Foundation. The Atoms for Peace Awards, it will be recalled, were established last summer as a memorial to Henry Ford ...

1955-10-29T23:59:59.000Z

447

Hirshfeld atom refinement  

Science Journals Connector (OSTI)

The new automated iterative Hirshfeld atom refinement method is explained and validated through comparison of structural models of Gly-L-Ala obtained from synchrotron X-ray and neutron diffraction data at 12, 50, 150 and 295 K. Structural parameters involving hydrogen atoms are determined with comparable precision from both experiments and agree mostly to within two combined standard uncertainties.

Capelli, S.C.

2014-08-29T23:59:59.000Z

448

Magneto-Optical Trapping of Holmium Atoms  

E-Print Network [OSTI]

We demonstrate sub-Doppler laser cooling and magneto-optical trapping of the rare earth element Holmium. Atoms are loaded from an atomic beam source and captured in six-beam $\\sigma_+ - \\sigma_-$ molasses using a strong $J=15/2 \\leftrightarrow J=17/2$ cycling transition at $\\lambda=410.5 \\rm nm$. Due to the small difference in hyperfine splittings and Land\\'e $g$-factors in the lower and upper levels of the cooling transition the MOT is self-repumped without additional repump light, and deep sub-Doppler cooling is achieved with the magnetic trap turned on. We measure the leakage out of the cycling transition to metastable states and find a branching ratio $\\sim 10^{-5}$ which is adequate for state resolved measurements on hyperfine encoded qubits.

J. Miao; J. Hostetter; G. Stratis; M. Saffman

2014-03-24T23:59:59.000Z

449

Informal Report . VAPOR DETECTION OF TRAFFICKING OF CONTRABAND MONEY-  

E-Print Network [OSTI]

I BNL- 62834 Informal Report . VAPOR DETECTION OF TRAFFICKING OF CONTRABAND MONEY-· [D VAPOR DETECTION OF TRAFFICKING OF CONTRABAND MONEY- A DISCUSSION OF TECHNICAL FEASIBILITY Concept MONEY --A DISCUSSION OF TECHNICAL FEASffiILITY Russell N. Dietz, Head Tracer Technology Center

450

RESONANT FARADAY ROTATION IN A HOT LITHIUM VAPOR  

E-Print Network [OSTI]

RESONANT FARADAY ROTATION IN A HOT LITHIUM VAPOR By SCOTT RUSSELL WAITUKAITIS A Thesis Submitted: #12;Abstract I describe a study of Faraday rotation in a hot lithium vapor. I begin by dis- cussing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3 The Lithium Oven and Solenoid . . . . . . . . . . . . . . . . . 7 3 Theoretical Framework

Cronin, Alex D.

451

Analysis of laser remote fusion cutting based on a mathematical model  

SciTech Connect (OSTI)

Laser remote fusion cutting is analyzed by the aid of a semi-analytical mathematical model of the processing front. By local calculation of the energy balance between the absorbed laser beam and the heat losses, the three-dimensional vaporization front can be calculated. Based on an empirical model for the melt flow field, from a mass balance, the melt film and the melting front can be derived, however only in a simplified manner and for quasi-steady state conditions. Front waviness and multiple reflections are not modelled. The model enables to compare the similarities, differences, and limits between laser remote fusion cutting, laser remote ablation cutting, and even laser keyhole welding. In contrast to the upper part of the vaporization front, the major part only slightly varies with respect to heat flux, laser power density, absorptivity, and angle of front inclination. Statistical analysis shows that for high cutting speed, the domains of high laser power density contribute much more to the formation of the front than for low speed. The semi-analytical modelling approach offers flexibility to simplify part of the process physics while, for example, sophisticated modelling of the complex focused fibre-guided laser beam is taken into account to enable deeper analysis of the beam interaction. Mechanisms like recast layer generation, absorptivity at a wavy processing front, and melt film formation are studied too.

Matti, R. S. [Department of Engineering Sciences and Mathematics, Luleå University of Technology, S-971 87 Luleå (Sweden); Department of Mechanical Engineering, College of Engineering, University of Mosul, Mosul (Iraq); Ilar, T.; Kaplan, A. F. H. [Department of Engineering Sciences and Mathematics, Luleå University of Technology, S-971 87 Luleå (Sweden)

2013-12-21T23:59:59.000Z

452

Atomic dark matter  

SciTech Connect (OSTI)

We propose that dark matter is dominantly comprised of atomic bound states. We build a simple model and map the parameter space that results in the early universe formation of hydrogen-like dark atoms. We find that atomic dark matter has interesting implications for cosmology as well as direct detection: Weak-scale dark atoms can accommodate hyperfine splittings of order 100 keV, consistent with the inelastic dark matter interpretation of the DAMA data while naturally evading direct detection bounds. Moreover, protohalo formation can be suppressed below M{sub proto} ? 10{sup 3}–10{sup 6}M{sub s}un for weak scale dark matter due to Ion-Radiation and Ion-Atom interactions in the dark sector.

Kaplan, David E.; Krnjaic, Gordan Z.; Rehermann, Keith R.; Wells, Christopher M., E-mail: dkaplan@pha.jhu.edu, E-mail: gordan@pha.jhu.edu, E-mail: keith@pha.jhu.edu, E-mail: cwells13@pha.jhu.edu [Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2686 (United States)

2010-05-01T23:59:59.000Z

453

FLAMMABILITY CHARACTERISTICS OF COMBUSTIBLE GASES AND VAPORS  

Office of Scientific and Technical Information (OSTI)

Bulletin 627 Bulletin 627 BUREAU o b MINES FLAMMABILITY CHARACTERISTICS OF COMBUSTIBLE GASES AND VAPORS By Michael G. Zabetakis DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency Thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement,

454

New Regenerative Cycle for Vapor Compression Refrigeration  

Office of Scientific and Technical Information (OSTI)

SCIENTIFIC REPORT SCIENTIFIC REPORT Title Page Project Title: New Regenerative Cycle for Vapor Compression Refrigeration DOE Award Number: DE-FG36-04GO14327 Document Title: Final Scientific Report Period Covered by Report: September 30, 2004 to September 30, 2005 Name and Address of Recipient Organization: Magnetic Development, Inc., 68 Winterhill Road, Madison, CT 06443, phone: 203-214-7247, fax: 203-421-7948, e-mail: mjb1000@aol.com Contact Information: Mark J. Bergander, Ph.D., P.E., Principal Investigator, phone: 203-214-7247, fax: 203-421-7948, e-mail: mjb1000@aol.com Project Objective (as stated in the proposal): The main objective of this project is to confirm on a well-instrumented prototype the theoretically derived claims of higher efficiency and coefficient

455

Formation energy of excess arsenic atoms in n-type GaAs  

Science Journals Connector (OSTI)

We report the first determination of the formation energy of excess-As-atom–related defects in Te-doped GaAs. The photocapacitance method in the constant-capacitance condition is applied to GaAs:Te prepared by 67-h annealing at 850–1100 °C under various As vapor pressures followed by rapid cooling. From an Arrhenius plot of the saturating deep-level density at quasi thermal equilibrium under high As vapor pressure, the formation energy of the defect is determined to be 1.16 eV in Te-doped horizontal-Bridgeman-grown GaAs crystals.

Jun-ichi Nishizawa; Yutaka Oyama; Kazushi Dezaki

1990-11-12T23:59:59.000Z

456

Gas Separation Using Organic-Vapor-Resistent Membranes In Conjunctin With Organic-Vapor-Selective Membranes  

DOE Patents [OSTI]

A process for treating a gas mixture containing at least an organic compound gas or vapor and a second gas, such as natural gas, refinery off-gas or air. The process uses two sequential membrane separation steps, one using membrane selective for the organic compound over the second gas, the other selective for the second gas over the organic vapor. The second-gas-selective membranes use a selective layer made from a polymer having repeating units of a fluorinated polymer, and demonstrate good resistance to plasticization by the organic components in the gas mixture under treatment, and good recovery after exposure to liquid aromatic hydrocarbons. The membrane steps can be combined in either order.

Baker, Richard W. (Palo Alto, CA); Pinnau, Ingo (Palo Alto, CA); He, Zhenjie (Fremont, CA); Da Costa, Andre R. (Menlo Park, CA); Daniels, Ramin (San Jose, CA); Amo, Karl D. (Mountain View, CA); Wijmans, Johannes G. (Menlo Park, CA)

2003-06-03T23:59:59.000Z

457

Hybrid Vapor Compression Adsorption System: Thermal Storage Using Hybrid Vapor Compression Adsorption System  

SciTech Connect (OSTI)

HEATS Project: UTRC is developing a new climate-control system for EVs that uses a hybrid vapor compression adsorption system with thermal energy storage. The targeted, closed system will use energy during the battery-charging step to recharge the thermal storage, and it will use minimal power to provide cooling or heating to the cabin during a drive cycle. The team will use a unique approach of absorbing a refrigerant on a metal salt, which will create a lightweight, high-energy-density refrigerant. This unique working pair can operate indefinitely as a traditional vapor compression heat pump using electrical energy, if desired. The project will deliver a hot-and-cold battery that provides comfort to the passengers using minimal power, substantially extending the driving range of EVs.

None

2012-01-04T23:59:59.000Z

458

Pressure dependence of phonons and excitons in InSe films prepared by metal-organic chemical vapor deposition  

Science Journals Connector (OSTI)

The pressure dependence of the Raman spectra of phase-pure InSe thin films prepared by the low-pressure metal-organic chemical vapor deposition technique has been studied using a diamond-anvil high-pressure cell. Enhancement in the intensities of the Raman modes has been observed as a result of pressure-induced “tuning” of the energy of the M1-type hyperbolic exciton in InSe at ?2.54 eV through discrete incident laser photon energies. The pressure coefficients of the phonon modes and of the hyperbolic exciton in InSe have been determined.

In-Hwan Choi and Peter Y. Yu

2003-10-27T23:59:59.000Z

459

Laser Desorption Analysis | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Desorption Analysis Laser Desorption Analysis EMSL offers a suite of instrumentation dedicated to understanding photoreactivity in the condensed phase, on surfaces, and at...

460

Laser Desorption Analysis | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

neutral particle detection using a second multiphoton ionization or REMPI laser system; and UHV surface diagnostic equipment (AES, LEED, XPS). User Portal Name: Laser...

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Laser Safety Management Policy Statement ............................................................................................................1  

E-Print Network [OSTI]

Laser Safety Management Policy Statement...........................................................2 Laser Users.............................................................................................................2 Unit Laser Safety Officer (ULSO

Davidson, Fordyce A.

462

Laser Stabilization  

SciTech Connect (OSTI)

This book chapter covers the basics of the field of stabilizing lasers to optical frequency references such as optical cavities and molecular transitions via the application of servo control systems. These discussions are given with reference to the real-life frequency metrology experienced in Hall-Labs (now Ye-Labs), JILA, University of Colorado. The subjects covered include: the basics of control system stability, a discussion of both the theoretical and experimental limitations, an outline of optical cavity susceptibility to environmental noise, and a brief introduction to the use and limitations of molecular transitions as frequency references.

Hall, John L.; Taubman, Matthew S.; Ye, Jun

2010-01-01T23:59:59.000Z

463

Omega Laser Facility - Laboratory for Laser Energetics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

- Laboratory for Laser Energetics Laboratory for Laser Energetics Logo Search Home Around the Lab Past Issues Past Quick Shots About Office of the Director Map to LLE LLE Tours LLE...

464

OMEGA Laser - Laboratory for Laser Energetics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

- Laboratory for Laser Energetics Laboratory for Laser Energetics Logo Search Home Around the Lab Past Issues Past Quick Shots About Office of the Director Map to LLE LLE Tours LLE...

465

OMEGA Laser Drivers - Laboratory for Laser Energetics  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Drivers - Laboratory for Laser Energetics Laboratory for Laser Energetics Logo Search Home Around the Lab Past Issues Past Quick Shots About Office of the Director Map to LLE LLE...

466

Enhanced absorption Hanle effect in the configuration of crossed laser beam and magnetic field F. Renzoni,1,  

E-Print Network [OSTI]

modifications of the absorptive and dispersive properties of atomic media 2­4 , and are responsible for the sub that increases the atomic absorption 8,9 . The increased atomic absorption, denoted as electromagnetic induced abEnhanced absorption Hanle effect in the configuration of crossed laser beam and magnetic field F

467

The laser satellites communications and laser noises  

Science Journals Connector (OSTI)

The gain of advanced optical communication systems is reduced by the noise of optical source. Coherent optical communication systems are in particular very sensitive to the noise transmitter and local laser. Optical space communications is on the verge ... Keywords: laser, laser communication, noise limits, optical communication, range loss, satellite communications, satellite systems, signal transfer loss, space channel

Marketa Mazalkova

2008-08-01T23:59:59.000Z

468

A graphene-based passively Q-switched Ho:YAG laser in-band pumped by a diode-pumped Tm:YLF solid-state laser  

Science Journals Connector (OSTI)

We report the first demonstration of a Ho:YAG (yttrium aluminum garnet) solid-state laser passively Q-switched via a graphene saturable absorber. The Ho:YAG laser was in-band pumped by a continuous wave diode-pumped Tm:YLF (yttrium lithium fluoride) laser. Double-layer graphene grown by chemical vapor deposition and transferred onto a thin quartz plate was fabricated as the saturable absorber. We observed basically stable Q-switched laser pulses at the center wavelength of 2096.5 nm with the shortest pulse width of 632 ns, a repetition rate of 43 kHz, and the single-pulse energy of 13.3 ?J. Our results illustrate that graphene can be used well as a saturable absorber in a Ho-doped solid-state laser at 2 ?m wavelength.

C J Jin; X M Chen; L F Li; M Qi; Y Bai; Z Y Ren; J T Bai

2014-01-01T23:59:59.000Z

469

A 674 nm external cavity diode laser for a ??Sr? ion trap  

E-Print Network [OSTI]

Atomic ion traps are a promising candidate for scalable quantum information processing. In this thesis, a 674 nm extended cavity diode laser is built to address an optical quantum bit in ??Sr? with the goal of testing such ...

Thon, Susanna M. (Susanna Mitrani)

2005-01-01T23:59:59.000Z

470

Underwater and water-assisted laser processing: Part 1—general features, steam cleaning and shock processing  

Science Journals Connector (OSTI)

Water is always present in laser processing in air: as vapor, condensate or adsorbate. Water is the working environment in underwater processing—but it can also be added on purpose to gain better results: to avoid redeposition of debris, to cool the material, to increase plasma pressure or to conduct light. Water can also act as a chemical reagent. The first part of the article will review the advantages and disadvantages of laser processing in the presence of water, light transmission by water, and the two most mature methods of water-assisted laser processing: steam cleaning and shock processing.

Arvi Kruusing

2004-01-01T23:59:59.000Z

471

Laser-processed three dimensional graphitic electrodes for diamond radiation detectors  

SciTech Connect (OSTI)

We have used an original approach for diamond detectors where three dimensional buried graphitic electrodes are processed in the bulk of a diamond substrate via laser-induced graphitization. Prototype made of polycrystalline chemical vapor deposition diamond was fabricated using a nanosecond UV laser. Its charge collection efficiency was evaluated using ?-particles emitted by a 241-Americium source. An improved charge collection efficiency was measured proving that laser micro-machining of diamond is a valid option for the future fabrication of three dimensional diamond detectors.

Caylar, Beno?-carett; Pomorski, Michal; Bergonzo, Philippe [CEA-LIST, Diamond Sensors Laboratory, Gif-sur-Yvette F-91191 (France)] [CEA-LIST, Diamond Sensors Laboratory, Gif-sur-Yvette F-91191 (France)

2013-07-22T23:59:59.000Z

472

3-D Atomic-Scale Mapping of Manganese Dopants in Lead Sulfide Nanowires  

SciTech Connect (OSTI)

Dopants in nanowires, whether intentional or unintentional, can ultimately control the material's properties and therefore need to be understood on the atomic scale. We study vapor-liquid-solid grown manganese-doped lead sulfide nanowires by atom-probe tomography for the first time for lead salt materials. The three-dimensional chemical concentration maps at the atomic scale demonstrate a radial distribution profile of Mn ions, with a concentration of only 0.18 at.% and 0.01 at.% for MnCl2 and Mn-acetate precursors, respectively. The ability to characterize these small concentrations of dopant atoms in Pb1-xMnxS nanowires (x = 0.0036 and 0.0002), important for spintronic and thermoelectric devices, sets a platform for similar analyses for all nanostructures. First-principles calculations confirm that Mn atoms substitute for Pb in the PbS structure.

Isheim, Dieter; Kaszpurenko, Jason; Yu, Dong; Mao, Zugang; Seidman, David N.; Arslan, Ilke

2012-03-22T23:59:59.000Z

473

Single-Photon Absorption in Coupled Atom-Cavity Systems  

E-Print Network [OSTI]

We show how to capture a single photon of arbitrary temporal shape with one atom coupled to an optical cavity. Our model applies to Raman transitions in three-level atoms with one branch of the transition controlled by a (classical) laser pulse, and the other coupled to the cavity. Photons impinging on the cavity normally exhibit partial reflection, transmission, and/or absorption by the atom. Only a control pulse of suitable temporal shape ensures impedance matching throughout the pulse, which is necessary for complete state mapping from photon to atom. For most possible photon shapes, we derive an unambiguous analytic expression for the shape of this control pulse, and we discuss how this relates to a quantum memory.

Jerome Dilley; Peter Nisbet-Jones; Bruce W. Shore; Axel Kuhn

2012-03-01T23:59:59.000Z

474

Optical analog of Rabi oscillation suppression due to atomic motion  

E-Print Network [OSTI]

The Rabi oscillations of a two-level atom illuminated by a laser on resonance with the atomic transition may be suppressed by the atomic motion through averaging or filtering mechanisms. The optical analogs of these velocity effects are described. The two atomic levels correspond in the optical analogy to orthogonal polarizations of light and the Rabi oscillations to polarization oscillations in a medium which is optically active, naturally or due to a magnetic field. In the later case, the two orthogonal polarizations could be selected by choosing the orientation of the magnetic field, and one of them be filtered out. It is argued that the time-dependent optical polarization oscillations or their suppression are observable with current technology.

J. G. Muga; B. Navarro

2005-05-13T23:59:59.000Z

475

general_atomics.cdr  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

former former General Atomics Hot Cell Facility was constructed in 1959 and operated until 1991. The site encompassed approximately 7,400 square feet of laboratory and remote operations cells. Licensed operations at the facility included receipt, handling, and shipment of radioactive materials; remote handling, examination, and storage of previously irradiated nuclear fuel materials; pilot-scale tritium extraction operations; and development, fabrication, and inspection of uranium oxide-beryllium oxide fuel materials. General Atomics performed most of the work for the federal government. The General Atomics Hot Cell Facility was located in a 60-acre complex 13 miles northwest of downtown San Diego, 1 mile inland from the Pacific Ocean, and approximately 300 feet above sea level. The General Atomics site is in the center of Torrey Mesa Science Center, a 304-acre industrial

476

Uncertainties on Atomic Data  

Science Journals Connector (OSTI)

Technical Paper / Selected papers from IAEA-NFRI Technical Meeting on Data Evaluation for Atomic, Molecular and Plasma-Material Interaction Processes in Fusion, September 4-7, 2012, Daejeon, Republic of Korea

C. P. Ballance; S. D. Loch; A. R. Foster; R. K. Smith; M. C. Witthoeft; T. R. Kallman

477

Relativistic Atomic Structure Calculations  

Science Journals Connector (OSTI)

This review surveys methods for computing the electronic structures of atoms based on the use of relativistic quantum mechanics. The main mathematical formulas are presented with some account of the underlying...

Ian P. Grant

1988-01-01T23:59:59.000Z

478

general_atomics.cdr  

Office of Legacy Management (LM)

300 feet above sea level. The General Atomics site is in the center of Torrey Mesa Science Center, a 304-acre industrial park. No ground water wells are at or near the Hot Cell...

479

The Harnessed Atom | Department of Energy  

Energy Savers [EERE]

Atom The Harnessed Atom The Harnessed Atom The Harnessed Atom is a new middle school science, technology, engineering, and math (STEM) curriculum extension that focuses on...

480

Optical imaging of Rydberg atoms .  

E-Print Network [OSTI]

??We present an experiment exploring electromagnetically induced transparency (EIT) in Rydberg atoms in order to observe optical nonlinearities at the single photon level. ??Rb atoms… (more)

Mazurenko, Anton

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "atomic vapor laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Rydberg Atoms for Quantum Information.  

E-Print Network [OSTI]

??I examine interactions between ensembles of cold Rydberg atoms, and between Rydberg atoms and an intense, optical standing wave. Because of their strong electrostatic interactions,… (more)

Younge, Kelly Cooper

2010-01-01T23:59:59.000Z

482

Metal atomization spray nozzle  

DOE Patents [OSTI]

A spray nozzle for a magnetohydrodynamic atomization apparatus has a feed passage for molten metal and a pair of spray electrodes mounted in the feed passage. The electrodes, diverging surfaces which define a nozzle throat and diverge at an acute angle from the throat. Current passes through molten metal when fed through the throat which creates the Lorentz force necessary to provide atomization of the molten metal. 6 figures.

Huxford, T.J.

1993-11-16T23:59:59.000Z

483

Population trapping in Kr and Xe in intense laser fields  

Science Journals Connector (OSTI)

We have observed trapping of population in Rydberg states of atoms and ions exposed to intense laser radiation. The trapping occurs in nonstationary ‘‘wave-packet’’ superposition states, created, via ac Stark-shifted multiphoton resonances during the laser pulse. The formation of these highly excited bound states requires the nonresonant absorption of up to 20 or more photons; some of the ionic Rydberg states lie nearly 32 eV above the ionic ground state. All of the trapped states having binding energies much less than the photon energy but remain stable against ionization even when the multiphoton ionization probability of the atom is saturated.

R. R. Jones; D. W. Schumacher; P. H. Bucksbaum

1993-01-01T23:59:59.000Z

484

Dopant induced ignition of helium nanodroplets in intense few-cycle laser pulses  

E-Print Network [OSTI]

We demonstrate ultrafast resonant energy absorption of rare-gas doped He nanodroplets from intense few-cycle (~10 fs) laser pulses. We find that less than 10 dopant atoms "ignite" the droplet to generate a non-spherical electronic nanoplasma resulting ultimately in complete ionization and disintegration of all atoms, although the pristine He droplet is transparent for the laser intensities applied. Our calculations at those intensities reveal that the minimal pulse length required for ignition is about 9 fs.

Krishnan, S R; Kremer, M; Sharma, V; Fischer, B; Camus, N; Jha, J; Krishnamurthy, M; Pfeifer, T; Moshammer, R; Ullrich, J; Stienkemeier, F; Mudrich, M; Mikaberidze, A; Saalmann, U; Rost, J -M

2011-01-01T23:59:59.000Z

485

Depth-Profiling and Diffusion Measurements in Ice Films Using Infrared Laser Resonant Desorption  

Science Journals Connector (OSTI)

The diffusion of several acids in ice including HCl,15-18 HNO3,16,18-20 and HF21,22 has also been studied using various techniques. ... The incident laser energy per volume required to convert H2O ice at 100 K to H2O vapor at 500 K can be calculated from the enthalpy of fusion (?Hfus) for H2O at 273 K, the enthalpy of vaporization (?Hvap) for H2O at 373 K, and the appropriate H2O heat capacities (Cp). ... The similarity between the results using the Er:YAG and Er:YSGG lasers in the Q-switched mode suggest that either laser can be used with equal effectiveness for corneal trephination. ...

Frank E. Livingston; Jamison A. Smith; Steven M. George

2000-10-10T23:59:59.000Z

486

ablation laser spectrometer  

E-Print Network [OSTI]

ablation laser mass spectrometer molecular beam REMPI laser NREL has designed and developed a combined laser ablation/ pulsed sample introduction/mass spectrometry platform that integrates pyrolysis and/or laser ablation with resonance- enhanced multiphoton ionization (REMPI) time-of-flight mass

487

Narrow gap laser welding  

DOE Patents [OSTI]

A laser welding process including: (a) using optical ray tracing to make a model of a laser beam and the geometry of a joint to be welded; (b) adjusting variables in the model to choose variables for use in making a laser weld; and (c) laser welding the joint to be welded using the chosen variables. 34 figs.

Milewski, J.O.; Sklar, E.

1998-06-02T23:59:59.000Z

488

Narrow gap laser welding  

DOE Patents [OSTI]

A laser welding process including: (a) using optical ray tracing to make a model of a laser beam and the geometry of a joint to be welded; (b) adjusting variables in the model to choose variables for use in making a laser weld; and (c) laser welding the joint to be welded using the chosen variables.

Milewski, John O. (Santa Fe, NM); Sklar, Edward (Santa Fe, NM)

1998-01-01T23:59:59.000Z

489

Short wavelength laser  

DOE Patents [OSTI]

A short wavelength laser is provided that is driven by conventional-laser pulses. A multiplicity of panels, mounted on substrates, are supported in two separated and alternately staggered facing and parallel arrays disposed along an approximately linear path. When the panels are illuminated by the conventional-laser pulses, single pass EUV or soft x-ray laser pulses are produced.

Hagelstein, P.L.

1984-06-25T23:59:59.000Z

490

Preliminary assessment of halogenated alkanes as vapor-phase tracers  

SciTech Connect (OSTI)

New tracers are needed to evaluate the efficiency of injection strategies in vapor-dominated environments. One group of compounds that seems to meet the requirements for vapor-phase tracing are the halogenated alkanes (HCFCs). HCFCs are generally nontoxic, and extrapolation of tabulated thermodynamic data indicate that they will be thermally stable and nonreactive in a geothermal environment. The solubilities and stabilities of these compounds, which form several homologous series, vary according to the substituent ratios of fluorine, chlorine, and hydrogen. Laboratory and field tests that will further define the suitability of HCFCs as vapor-phase tracers are under way.

Adams, Michael C.; Moore, Joseph N.; Hirtz, Paul

1991-01-01T23:59:59.000Z

491

Mercury Vapor At Medicine Lake Area (Kooten, 1987) | Open Energy  

Open Energy Info (EERE)

Kooten, 1987) Kooten, 1987) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Mercury Vapor At Medicine Lake Area (Kooten, 1987) Exploration Activity Details Location Medicine Lake Area Exploration Technique Mercury Vapor Activity Date Usefulness could be useful with more improvements DOE-funding Unknown References Gerald K. Van Kooten (1987) Geothermal Exploration Using Surface Mercury Geochemistry Retrieved from "http://en.openei.org/w/index.php?title=Mercury_Vapor_At_Medicine_Lake_Area_(Kooten,_1987)&oldid=386431" Category: Exploration Activities What links here Related changes Special pages Printable version Permanent link Browse properties 429 Throttled (bot load) Error 429 Throttled (bot load) Throttled (bot load) Guru Meditation:

492

Atomic population distribution in the output ports of cold-atom interferometers with optical splitting and recombination  

SciTech Connect (OSTI)

Cold-atom interferometers with optical splitting and recombination use off-resonant laser beams to split a cloud of Bose-Einstein condensate (BEC) into two clouds that travel along different paths and are then recombined again using optical beams. After the recombination, the BEC in general populates both the cloud at rest and the moving clouds. Measuring a relative number of atoms in each of these clouds yields information about the relative phase shift accumulated by the atoms in the two moving clouds during the interferometric cycle. We derive the expression for the probability of finding any given number of atoms in each of the clouds, discuss features of the probability density distribution, analyze its dependence on the relative accumulated phase shift as a function of the strength of the interatomic interactions, and compare our results with experiment.

Ilo-Okeke, Ebubechukwu O.; Zozulya, Alex A. [Department of Physics, Worcester Polytechnic Institute, 100 Institute Road, Worcester, Massachusetts 01609 (United States)

2010-11-15T23:59:59.000Z

493

Atomic mass compilation 2012  

SciTech Connect (OSTI)

Atomic mass reflects the total binding energy of all nucleons in an atomic nucleus. Compilations and evaluations of atomic masses and derived quantities, such as neutron or proton separation energies, are indispensable tools for research and applications. In the last decade, the field has evolved rapidly after the advent of new production and measuring techniques for stable and unstable nuclei resulting in substantial ameliorations concerning the body of data and their precision. Here, we present a compilation of atomic masses comprising the data from the evaluation of 2003 as well as the results of new measurements performed. The relevant literature in refereed journals and reports as far as available, was scanned for the period beginning 2003 up to and including April 2012. Overall, 5750 new data points have been collected. Recommended values for the relative atomic masses have been derived and a comparison with the 2003 Atomic Mass Evaluation has been performed. This work has been carried out in collaboration with and as a contribution to the European Nuclear Structure and Decay Data Network of Evaluations.

Pfeiffer, B., E-mail: bpfeiffe@uni-mainz.de [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); Venkataramaniah, K. [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India)] [Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam (India); Czok, U. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany)] [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); Scheidenberger, C. [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany) [GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt (Germany); II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany)

2014-03-15T23:59:59.000Z

494

Laser Glazing of Railroad Rails [Laser Applications Laboratory] - Nuclear  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Glazing of Railroad Laser Glazing of Railroad Rails Capabilities Engineering Experimentation Reactor Safety Experimentation Aerosol Experiments System Components Laser Applications Overview Laser Oil & Gas Well Drilling Laser Heat Treatment Laser Welding of Metals On-line Monitoring Laser Beam Delivery Laser Glazing of Railroad Rails High Power Laser Beam Delivery Decontamination and Decommissioning Refractory Alloy Welding Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Laser Applications Laboratory Laser Glazing of Railroad Rails Project description: Laser glazing of rails. Category: Project with industrial partner (American Association of Railroads) Bookmark and Share

495

Laser Welding of Metals [Laser Applications Laboratory] - Nuclear  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Welding of Metals Laser Welding of Metals Capabilities Engineering Experimentation Reactor Safety Experimentation Aerosol Experiments System Components Laser Applications Overview Laser Oil & Gas Well Drilling Laser Heat Treatment Laser Welding of Metals On-line Monitoring Laser Beam Delivery Laser Glazing of Railroad Rails High Power Laser Beam Delivery Decontamination and Decommissioning Refractory Alloy Welding Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Laser Applications Laboratory Laser Welding of Metals Project description: High-speed laser welding of metals. Category: Project with industrial partner (Delphi Energy and Engine Management Systems) Bookmark and Share

496

Light-induced gauge fields for ultracold atoms  

E-Print Network [OSTI]

Gauge fields are central in our modern understanding of physics at all scales. At the highest energy scales known, the microscopic universe is governed by particles interacting with each other through the exchange of gauge bosons. At the largest length scales, our universe is ruled by gravity, whose gauge structure suggests the existence of a particle - the graviton - that mediates the gravitational force. At the mesoscopic scale, solid-state systems are subjected to gauge fields of different nature: materials can be immersed in external electromagnetic fields, but they can also feature emerging gauge fields in their low-energy description. In this review, we focus on another kind of gauge field: those engineered in systems of ultracold neutral atoms. In these setups, atoms are suitably coupled to laser fields that generate effective gauge potentials in their description. Neutral atoms "feeling" laser-induced gauge potentials can potentially mimic the behavior of an electron gas subjected to a magnetic field, but also, the interaction of elementary particles with non-Abelian gauge fields. Here, we review different realized and proposed techniques for creating gauge potentials - both Abelian and non-Abelian - in atomic systems and discuss their implication in the context of quantum simulation. While most of these setups concern the realization of background and classical gauge potentials, we conclude with more exotic proposals where these synthetic fields might be made dynamical, in view of simulating interacting gauge theories with cold atoms.

N. Goldman; G. Juzeliunas; P. Ohberg; I. B. Spielman

2014-12-12T23:59:59.000Z

497

Catalytic Reactor For Oxidizing Mercury Vapor  

DOE Patents [OSTI]

A catalytic reactor (10) for oxidizing elemental mercury contained in flue gas is provided. The catalyst reactor (10) comprises within a flue gas conduit a perforated corona discharge plate (30a, b) having a plurality of through openings (33) and a plurality of projecting corona discharge electrodes (31); a perforated electrode plate (40a, b, c) having a plurality of through openings (43) axially aligned with the through openings (33) of the perforated corona discharge plate (30a, b) displaced from and opposing the tips of the corona discharge electrodes (31); and a catalyst member (60a, b, c, d) overlaying that face of the perforated electrode plate (40a, b, c) opposing the tips of the corona discharge electrodes (31). A uniformly distributed corona discharge plasma (1000) is intermittently generated between the plurality of corona discharge electrode tips (31) and the catalyst member (60a, b, c, d) when a stream of flue gas is passed through the conduit. During those periods when corona discharge (1000) is not being generated, the catalyst molecules of the catalyst member (60a, b, c, d) adsorb mercury vapor contained in the passing flue gas. During those periods when corona discharge (1000) is being generated, ions and active radicals contained in the generated corona discharge plasma (1000) desorb the mercury from the catalyst molecules of the catalyst member (60a, b, c, d), oxidizing the mercury in virtually simultaneous manner. The desorption process regenerates and activates the catalyst member molecules.

Helfritch, Dennis J. (Baltimore, MD)

1998-07-28T23:59:59.000Z

498

The focusing effect of cold atomic cloud with a red-detuned Gaussian beam  

E-Print Network [OSTI]

We have demonstrated an atom-optical lens, with the advantage of a small scale and flexible adjustment of the parameters, realized by a far red-detuned Gaussian laser beam perpendicular to the propagation direction of the cold atomic cloud. The one-dimensional transverse focusing effect of cold atomic clouds at the temperature order of 1 $\\mu$K freely falling through the atom-optical lens on the micron scale have been studied theoretically and then verified experimentally. It is found that theory and experiment are in good agreement.

Zhenglu Duan; Shuyu Zhou; Tao Hong; Yuzhu Wang

2015-01-28T23:59:59.000Z

499

FeP precipitates in hydride?vapor phase epitaxially grown InP:Fe  

Science Journals Connector (OSTI)

Fe?doped InP was grown by hydride?vapor phase epitaxy.Doping levels up to 8×1018 cm?3 were determined by secondary ion mass spectrometry. Additionally performed photoluminescence measurements revealed a homogeneous distribution of electrically active Fe atoms. From microstructural investigations by analytical transmission electron microscopy spherical?shaped precipitates were detected in plan?view samples. These precipitates with diameters up to 13 nm are homogeneously arranged in the epilayer. For conglomerates of precipitates a distinct enrichment with Fe and P was measured by a comparative energy dispersive x?ray analysis. The lattice plane distances of the precipitates were deduced from the electron diffraction patterns and from high?resolution electron micrographs. A comparison with calculated values for different Fe–P alloys indicates that the precipitates consist mainly of orthorhombic FeP.

M. Luysberg; R. Göbel; H. Janning

1994-01-01T23:59:59.000Z

500

Plasma-enhanced chemical vapor deposition of graphene on copper substrates  

SciTech Connect (OSTI)

A plasma enhanced vapor deposition process is used to synthesize graphene from a hydrogen/methane gas mixture on copper samples. The graphene samples were transferred onto SiO{sub 2} substrates and characterized by Raman spectroscopic mapping and atomic force microscope topographical mapping. Analysis of the Raman bands shows that the deposited graphene is clearly SLG and that the sheets are deposited on large areas of several mm{sup 2}. The defect density in the graphene sheets is calculated using Raman measurements and the influence of the process pressure on the defect density is measured. Furthermore the origin of these defects is discussed with respect to the process parameters and hence the plasma environment.

Woehrl, Nicolas, E-mail: nicolas.woehrl@uni-due.de; Schulz, Stephan [Faculty of Chemistry and CENIDE, University Duisburg-Essen, Carl-Benz-Straße 199, 47057 Duisburg (Germany)] [Faculty of Chemistry and CENIDE, University Duisburg-Essen, Carl-Benz-Straße 199, 47057 Duisburg (Germany); Ochedowski, Oliver; Gottlieb, Steven [Faculty of Physics and CENIDE, University Duisburg Essen, Lotharstraße 1, 47057 Duisburg (Germany)] [Faculty of Physics and CENIDE, University Duisburg Essen, Lotharstraße 1, 47057 Duisburg (Germany); Shibasaki, Kosuke [Institute of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan)] [Institute of Materials Science, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8573 (Japan)

2014-04-15T23:59:59.000Z