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Displaying 551 - 575 of 672

Superradiance of cold atoms coupled to a superconducting circuit

June 6, 2011
Author(s)
Daniel Braun, Jonathan Hoffman, Eite Tiesinga
We investigate superradiance of an ensemble of atoms coupled to an integrated superconducting LC-circuit. Particular attention is paid to the effect of inhomogeneous coupling constants. Combining perturbation theory in the inhomogeneity and numerical

Recent progress in spectroscopy of tungsten

May 20, 2011
Author(s)
Alexander Kramida
This contribution reviews experimental and theoretical work on spectroscopy of tungsten published since the last critical compilation of the energy levels and spectral lines of highly ionized tungsten [K09]. Since then, 15 new experimental studies were

Recent developments in the NIST Atomic Databases

May 11, 2011
Author(s)
Alexander Kramida
New versions of the NIST Atomic Spectra Database (ASD, v. 4.0) and three bibliographic databases (Atomic Energy Levels and Spectra, v. 2.0, Atomic Transition Probabilities, v. 9.0, and Atomic Line Broadening and Shapes, v. 3.0) have recently been released

Spatial separation in a thermal mixture of ultracold174Yb and 87Rb atoms

April 21, 2011
Author(s)
F. Baumer, F. Munchow, A. Gorlitz, Stephen Maxwell, Paul S. Julienne, Eite Tiesinga
We report on the observation of unusually strong interactions in a thermal mixture of ultracold atoms which cause a significant modification of the spatial distribution. A mixture of 87Rb and 174Yb with a temperature of a few μK is prepared in a hybrid

Feshbach spectroscopy and analysis of the interaction potentials of ultracold sodium

April 8, 2011
Author(s)
T. Schuster, R. Scelle, A. Trautmann, J. Appmeier, S. Knoop, Eite Tiesinga, E. Tiemann
We have studied magnetic Feshbach resonances in an ultracold sample of Na prepared in the absolute hyperfine ground. W e report on the observation of three s-, eight d-, and three g-wave Feshbach resonances, including a more precis e determination of the

Time Dependent Acceleration Measurements Through Synthetic Gauge Fields

March 3, 2011
Author(s)
Brandon Anderson, Jacob Taylor, Victor Galitski
We propose an atom interferometry scheme for measuring weak, time- dependent accelerations. Our proposal uses an ensemble of dilute bosons with two internal states that couple to a synthetic gauge field with opposite charges. The gauge field couples spin to

Thermal Correction to the Molar Polarizability of a Boltzmann Gas (Brief Report)

March 1, 2011
Author(s)
Ulrich D. Jentschura, M. Puchalski, Peter Mohr
The metrology of fundamental quantities in atomic physics has been crucial for a number of advanced determinations of fundamental constants. In addition to very accurate frequency measurements, the molar polarizability of atomic gases has recently been

The program LOPT for least-squares optimization of energy levels

February 1, 2011
Author(s)
Alexander Kramida
The article describes a program that solves the least-squares optimization problem for finding the energy levels of a quantum-mechanical system based on a set of measured energy separations or wavelengths of transitions between those energy levels, as well

Femtotesla atomic magnetometry in a microfabricated vapor cell

December 20, 2010
Author(s)
William C. Griffith, Svenja A. Knappe, John Kitching
We describe an optically pumped 87Rb magnetometer with 4.5 fT/Hz 1/2 sensitivity when operated in the spin-exchange relaxation free (SERF) regime. The magnetometer uses a microfabricated vapor cell, consisting of a cavity etched in a 1 mm thick silicon

Progress at NIST in measuring the D-lines of Li isotopes using an optical frequency comb

December 20, 2010
Author(s)
Clayton Simien, Samuel M. Brewer, Joseph N. Tan, John D. Gillaspy, Craig J. Sansonetti
Precise spectroscopic experiments with light atoms can provide information about nuclear properties that are very difficult to obtain in electron scattering experiments. For example, relative nuclear radii of low-Z isotopes can be determined accurately

Low loss superconducting titanium nitride coplanar waveguide resonators

December 9, 2010
Author(s)
Michael Vissers, Jiansong Gao, David S. Wisbey, David P. Pappas, C. C. Tsuei, A. D. Corcoles, Matthias Steffen
Thin films of TiN were sputter-deposited onto Si and sapphire wafers with and without SiN buffer layers. The films were fabricated into RF coplanar waveguide resonators, and internal quality factor measurements were taken at millikelvin temperatures in

Decoherence due to elastic Rayleigh scattering

November 12, 2010
Author(s)
Hermann Uys, Michael J. Biercuk, Aaron Vandevender, Christian Ospelkaus, Dominic Meiser, R. Ozeri, John Bollinger
We present theoretical and experimental studies of the decoherence of hyperfine ground-state superpositions due to elastic Rayleigh scattering of off-resonant light. We demonstrate that under appropriate conditions, elastic Rayleigh scattering can be the

A Microwave Study of Hydrogen-Transfer-Triggered Methyl-Group Rotation in 5-Methyltropolone

November 10, 2010
Author(s)
Vadim V. Ilyushin, Emily A. Cloessner, Yung-Ching Chou, Laura B. Picraux, Jon T. Hougen, Richard Lavrich
We present here the first experimental and theoretical study of the microwave spectrum of 5-methyltropolone, which can be visualized as a 7-membered aromatic carbon ring with a five-membered hydrogen-bonded cyclic structure at the top and a methyl group at

Consistency of atomic data for the interpretation of beam emission spectra

November 8, 2010
Author(s)
E. Delabie, M. Brix, R. J. Jasper, C. Giroud, O. Marchuk, M. G. O'Mullane, Yuri Ralchenko, E Surrey, M. G. von Hellermann, K. Zastrow, JET-EFDA Contributors
Several collisional-radiative (CR) models \citeanderson,hutchinson,marchuk:htpd} have been developed to calculate the attenuation and the population of excited states of hydrogen or deuterium beams injected into tokamak plasmas. The datasets generated by

A comprehensive analysis of the spectrum of Fe II

October 28, 2010
Author(s)
Gillian Nave
A new analysis of the laboratory spectrum of Fe II is described. The aim is to produce a comprehensive list of Fe II lines, based on high-resolution grating and Fourier transform spectra, covering wavelengths from 900 ̊A to 5.5 μm. Particular attention has

Atomic Spectroscopic Databases at NIST

October 28, 2010
Author(s)
Joseph Reader, Alexander Kramida, Yuri Ralchenko
We present recent work at NIST to develop and maintain databases for spectra, transition probabilities, and energy levels of atoms that are astrophysically important. We also describe our programs to critically compile these data as well as the recently

Towards More Accurate Atomic Oscillator Strengths

October 28, 2010
Author(s)
Wolfgang L. Wiese, Jeffrey R. Fuhr, John M. Bridges
Accurate determinations of atomic oscillator strengths have been a problem for a long time, and discrepancies between various numerical results have been substantial. But in recent years considerable progress has been made, especially for weak lines

Revised interpretation of the Na I EUV absorption spectrum

September 27, 2010
Author(s)
Alexander Kramida
Spectral data for neutral sodium were recently compiled by Sansonetti (2008 J. Phys. Chem. Ref. Data 37 1659). In that compilation, some of the energy levels of the 2p53snl configurations were quoted from the studies of the absorption spectrum in the

yocto-Newton force detection sensitivity using trapped ions

August 22, 2010
Author(s)
Michael J. Biercuk, Joseph W. Britton, Hermann Uys, Aaron Vandevender, John Bollinger
Recent experimental advances have shown that it is possible to detect forces arising from electric fields at a level of aN/ √Hz (atto = 10 -18 through coupling of micro or nanofabricated mechanical resonators to a variety of physical systems including

Coherent spin manipulation in an exchange-only qubit

August 4, 2010
Author(s)
E. A. Laird, Jacob Taylor, David P. DiVincenzo, C. M. Marcus, M. P. Hanson, A. C. Gossard
Initialization, manipulation and measurement of a three-spin qubit are demonstrated using a few- electron triple quantum dot, where all operations can be driven by tuning the exchange interaction. Multiplexed reflectometry, applied to two nearby charge

Resolved sideband emission from dynamically strained quantum dots

July 16, 2010
Author(s)
Michael Metcalfe, Stephen M. Carr, Andreas Muller, Glenn S. Solomon, John R. Lawall
The dynamic response of InAs/GaAs self-assembled quantum dots (QDs) to strain is studied by periodically modulating the QDs with a surface acoustic wave (SAW) and measuring the QD fluorescence with both photoluminescence and resonant spectroscopy. When the

Ultrahigh finesse low mode volume Fabry-Perot microcavity

July 1, 2010
Author(s)
Andreas Muller, Edward B. Flagg, John R. Lawall, Glenn S. Solomon
Ultralow loss concave micromirrors with radii of curvature below 60 um were fabricated by laser ablation and reflective coatings. A 10 um long microcavity with a mode volume of 40 um^3 was set up with two such mirrors and the cavity linewidth measured both
Displaying 551 - 575 of 672
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