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John J. Curry, Albert Henins, E. G. Estupinan, W. P. Lapatovich, S. D. Shastri
X-ray induced fluorescence is demonstrated as a fast and accurate method for measuring elemental vapor pressures over a wide range of pressures. As such, it may offer a preferable alternative to existing methods such as those based on effusion
The comment by W. Ketterle [1] purports having a viable model of superradiance. However, Ref. [1] admits not being able to explain the red/blue pump detuning asymmetry in matter-wave superradiance that was first observed recently by us [2]. It is clear
Kenton R. Brown, Christian Ospelkaus, Yves Colombe, Andrew C. Wilson, Dietrich G. Leibfried, David J. Wineland
The harmonic oscillator is one of the simplest physical systems but also one of the most fundamental. It is ubiquitous in nature, often serving as an approximation for a more complicated system or as a building block for larger models. Realizations of
Paul C. DeRose, Melody V. Smith, Klaus Mielenz, Jeffrey R. Anderson, Gary W. Kramer
Standard Reference Material (SRM) 2942 is a cuvette-shaped, Ce-ion-doped glass, recommended for use for relative spectral correction of emission and day-to-day performance verification of steady-state fluorescence spectrometers. Properties of this standard
Michael A. Lombardi, Andrew N. Novick, J. Mauricio Lopez-Romero, Francisco Jimenez, Eduardo de Carlos Lopez, Jean-Simon Boulanger, Raymond Pelletier, Ricardo de Carvalho, Raul Solis, Harold Sanchez, Carlos A. Quevedo, Gregory Pascoe, Daniel Perez, Eduardo Bances, Leonardo Trigo, Victor Masil, Henry Postigo, Anthony Questelles
The Sistema Interamericano de Metrologia (SIM) is a regional metrology organization (RMO) whose members are the national metrology institutes (NMIs) located in the 34 nations of the Organization of American States (OAS). The SIM/OAS region extends
This paper reports effects of inter-film interactions on static and dynamic magnetization behavior at film edges in magnetic trilayer stripe arrays under transverse applied fields. The trilayers consist of two magnetic films of Ni80Fe20, 10 nm and 20 nm
John D. Gillaspy, E. H. Silver, L. Tedesco, Joseph N. Tan, Joshua M. Pomeroy, J M. Laming, G.-X. Chen, T. Lin
New laboratory measurements of the Ne-like Fe xvii x-ray lines in the 15-17 Angstrom range are presented, along with new theoretical predictions. These results establish consistency between independent laboratories and opens the door to trustworthy
Meng Zhu, Brian D. Soe, Robert D. McMichael, Matthew Carey, Stefan Maat, Jeffrey R. Childress
A spin wave Doppler technique is used to measure the drift velocity of the magnetization in current-carrying (CoFe)_{1-x}Ge_{x} alloys. For a current density of 10^11 A/m2, we obtain a large enhancement of drift velocity from 3.1+/-0.2 m/s for CoFe to 8.2+
There are numerous medical conditions which may benefit from hyperspectral imaging. The imagers used for these conditions will need to have the performance validated to ensure consistency, gain acceptance and clear regulatory hurdles. NIST has been
David R. Leibrandt, Michael J. Thorpe, Mark Notcutt, Robert E. Drullinger, Till P. Rosenband, James C. Bergquist
We present an ultra-stable optical cavity design that is insensitive to both vibrations and orientation. The design is based on a spherical cavity spacer which is held rigidly at two points on a diameter of the sphere. Coupling of the support forces to the
When a mixture of ethylene in a large excess of neon is codeposited at 4.3 K with a beam of neon atoms that have been excited in a microwave discharge, two groups of product absorptions appear in the infrared spectrum of the deposit. Similar studies using
Jennifer A. Taylor, Shubahshish Datta, Archita Hati, Craig W. Nelson, Franklyn J. Quinlan, Abhay Joshi, Scott A. Diddams
Fluctuations of the optical power incident on a photodiode can be converted into phase fluctuations of the resulting electronic signal due to nonlinear saturation in the semiconductor. This impacts overall timing stability (phase noise) of microwave
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
Gillian Nave, Craig J. Sansonetti, Csilla Szabo, John J. Curry, Darren Smillie
We describe the use of phosphor image plates for recording spectra in the vacuum ultraviolet (VUV) and for determining accurate relative and absolute intensities. We investigated the spatial uniformity, noise level, linearity of the response to VUV light
The use of trapped atomic ions in the field of quantum information processing is briefly reviewed. We summarize the basic mechanisms required for logic gates and the use of the gates in demonstrating simple algorithms. We discuss the potential of trapped
Andrew D. Ludlow, Yanyi Jiang, Nathan D. Lemke, Richard W. Fox, Jeffrey A. Sherman, Long-Sheng Ma, Christopher W. Oates
The superb precision of an atomic clock is derived from its stability. Atomic clocks based on optical (rather than microwave) frequencies are attractive because of their potential for high stability, which scales with operational frequency. Nevertheless
David L. VanderHart, Jack F. Douglas, Steven Hudson, Joseph M. Antonucci, Elizabeth A. Wilder
The molecule 1,3:2,4-Di-O-Benzylidene sorbitol (DBS) is a common gelator that forms thermally reversible gels in diverse organic solvents. Solid state 13C and proton NMR techniques, along with electron microscopy, are utilized in an exploratory study of
Ilija Draganic, Yuri Ralchenko, Joseph Reader, John D. Gillaspy, Joseph N. Tan, Joshua M. Pomeroy, Samuel M. Brewer, Dmitry D. Osin
Extreme ultraviolet spectra of highly charged hafnium, tantalum, and gold were produced with an electron beam ion trap (EBIT) at the National Institute of Standards and Technology (NIST) and recorded with a flat-field grazing-incidence spectrometer in the
The Time and Frequency Bulletin provides information on performance of time scales and a variety of broadcasts (and related information) to users of the NIST services.
Svenja A. Knappe, Jan Preusser, Lutz Trahms, Tillman H. Sander
This an article in German for a general physics Journal. It is not peer reviewed and reports on the NIST chip-scale atomic magnetometers and the MCG measurements that were recently published in APL.
We describe the use of x-ray induced fluorescence to study metal-halide high-intensity discharge lamps and to measure equilibrium vapor pressures of metal-halide salts. The physical principles of metal-halide lamps, relevant aspects of x ray - atom
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
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
A M. Micherdzinska, C. D. Bass, T. D. Bass, K. F. Gan, D Lou, D M. Markoff, Hans Pieter Mumm, Jeffrey S. Nico, A. K. Opper, E I. Sharapov, M Snow, H E. Swanson, V Zhumabekova
Measurements of parity-violating neutron spin rotation can provide insight into the poorly nderstood nucleon-nucleon weak interaction. Because the expected rotation angle per unit length is small (10−7 rad/m), several properties of the polarized cold
In this paper, we will provide an overview of the internal photoemission (IPE) and the significance of this technique when combined with spectroscopic ellipsometry (SE) to investigate the interfacial electronic properties of heterostructures. In particular