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Allan H. Harvey, Akyl S. Tulegenov, Richard J. Wheatley, Matthew P. Hodges
We construct a rigid-body (five-dimensional) potential-energy surface for the water-nitrogen complex using the systematic intermolecular potential extrapolation routine (SIMPER). The intermolecular potential is then extrapolated to the limit of a complete
In October 2005, a 2-day follow up workshop, Single photon: sources, detectors, applications and measurement methods, was held at the NPL (National Physical Laboratory, UK). The focus for this workshop was to report on the key developments since the
Comparison of plasma population kinetics codes, which has become an important tool for their testing and verification, was the subject of the 3rd Non-LTE Code Comparison Workshop held at the National Institute of Standards and Technology in December 2003
Jean-Marie Flaud, Walter J. Lafferty, F. Kwabia Tchana
Using high-resolution Fourier transform spectra of propane recorded in the 13.4 μm (resolution of 0.002 cm-1) and in the 27.4 μm (resolution 0.0011 cm-1) spectral regions, it was possible to perform a thorough assignment of both the ν26 band at 745 cm-1
Energy levels, with classifications and uncertainties, have been compiled for the spectra of the neutral atom and all positive ions of rubidium (Z=37). Wavelengths with classifications, intensities, and transition probabilities are also tabulated. In
We analyze a lifetime-broadened four-state four-wave-mixing (FWM) scheme in the ultraslow propagation regime and show that the generated FWM field can acquire the same group velocity and pulse shape as those of an ultraslow pump field. We show that a new
We show the formation of ultraslow bright and dark optical solitons in a lifetime-broadened three-state atomic system under Raman excitation. We also discuss why such ultraslow optical solitons may not exist under the conditions of the usual
A surface magneto-optical trap for chromium atoms is demonstrated as a first step toward loading atoms into microscopic magnetic traps. Characteristics of the trap and transfer to microscopic magnetic traps will be discussed.
A magneto-optic trap with feedback-controlled loading and loss rates is used to realize a deterministic source of single Cr atoms with single-atom occupation probability as high as 0.987 plus or minus} 0.001. We present a series of measurements of the
We propose a scheme to achieve the entanglement of N photon modes (frequency modes) with perfectly efficient ultraslow multiwave mixing in a cold atomic medium. In addition, the method provides an efficient approach to realizing frequency tunability.
M P. Hodges, R J. Wheatley, G K. Schenter, Allan H. Harvey
We construct a rigid-body (5-dimensional) potential-energy surface for the water-hydrogen complex using scaled perturbation theory (SPT). An analytic fit of this surface is obtained, and using this, two minima are found: the global miniumum has C 2v
We have realized a method for producing single Cr atoms on demand by suppressing the stochastic nature of the loading and loss processes of a magneto-optic trap. We observe single-atom trap occupation probabilities as high as (98.7 plus or minus} 0.1)% and
E Silver, H. Schnopper, Simon R. Bandler, N Brickhouse, S Murray, M Barbera, E Takacs, John D. Gillaspy, James V. Porto, I Kink, J M. Laming, N. Madden, D Landis, J. Beeman, E. E. Haller
Cosmic plasma conditions created in an Electron Beam Ion Trap (EBIT) make it possible to simulate the dependencies of Key diagnostic x-ray lines on density, temperature, and excitation conditions that exist in astrophysical sources. We used a
C Bradley, Jabez J. McClelland, W Anderson, Robert Celotta
We have constructed a magneto-optical trap for chromium atoms. Using trapping light at 425 nm and two repumping lasers tuned to intercombination transitions, over 10 6 atoms were trapped and average densities of over 10 16 m -3 were obtained. Non
Eric Dauler, Gregg Jaeger, A Muller, Alan L. Migdall
An investigation is made of a recently introduced quantum interferometric method capable of measuring polarization mode dispersion (PMD) on sub-femtosecond scales, without the usual interferometric stability problems associated with such small time scales
V D. Kleiman, Edwin J. Heilweil, D McMorrow, Joseph S. Melinger
Chirped ultrafast laser pulses in the mid-Infrared and visible are used to experimentally control population transfer in condensed-phase systems and molecules.
Ion traps allow researchers to control the position and movement of charged particles with exquisite precision, and provide a powerful way to study many atomic phenomena.
R E. Scholten, R Gupta, Jabez J. McClelland, Robert Celotta, M Levenson, M Vangel
We have studied laser collimation of a chromium atomic beam using a transverse polarization gradient cooling scheme. We present detailed measurements of the angular distribution of atoms on the beam axis, over a broad range of laser intensities and
Svetlana A. Kotochigova, Zachary H. Levine, Eric L. Shirley, Mark D. Stiles, Charles W. Clark
The total energies of atoms and with atomic number Ζ from 1 to 92 and singly-charge cations with Ζ from 2 to 92 have been calculated to an accuracy of 1 υHartree within four variants of the Kohn-Sham local-density approximation. The approximations
G Hanne, Jabez J. McClelland, R E. Scholten, Robert Celotta
Superelastic scattering of polarized electrons from laser-excited polarized chromium atoms (4 7P o 4 rarr} 4 7S 3 transition, energy gain 2.92 eV) has been measured for total collision energies of 6.8 and 13.6 eV (0.5 and 1.0 Ryd) and scattering angles
Kevin Coakley, Jabez J. McClelland, Michael H. Kelley, Robert Celotta
In many scattering experiments, the quantity of most direct physical interest is a measure of the difference between two closely related scattering signals, each generated by a Poisson scattering process. This difference is often expressed in terms of an