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D. G. Smillie, J C. Pickering, Gillian Nave, P. L. Smith
The spectrum of Co III has been recorded in the region 1562 Å to 2564 Å 64000 cm-1 to 39 000 cm-1 by Fourier transform (FT) spectroscopy, and in the region 1317 Å to 2500 Å (164 000 cm-1 to 40 000 cm-1) using a 10.7 m grating spectrograph with phosphor
Abram Van Der Geest, Katie Hurst, John H. Lehman, Mark T. Lusk
It has been experimentally observed that amorphous carbon is removed from as-prepared, bulk, single-walled carbon nanotubes by illumination with 248 nm (5 eV) UV light. The process via which this occurs, though, has not yet been rigorously identified. We
Brad Conrad, Calvin Chan, Marsha A. Loth, John E. Anthony, David J. Gundlach
We will discuss the growth and electrical measurements of a newly developed, partially fluorinated anthradithiophene (F-ADT) derivative with tert-butyldiphenylsilyl (TBDMS) side groups. Single crystals of the material can be readily grown and device hole
Jason Amini, Hermann Uys, Janus H. Wesenberg, Signe Seidelin, Joseph W. Britton, John J. Bollinger, Dietrich G. Leibfried, Christian Ospelkaus, Aaron Vandevender, David J. Wineland
The basic components for a quantum information processor using trapped ions have been demonstrated in a number of experiments. To perform complex algorithms that are not tractable with classical computers, these components need to be integrated and scaled
Aaron Pearlman, Alexander E. Ling, Elizabeth A. Goldschmidt, Jingyun Fan, Christoph Wildfeuer, Alan L. Migdall
We experimentally map the transverse profile of diffraction-limited beams using photon number resolving detectors. We observe strong compression of diffracted beam profiles for high detected photon number. This effect leads to higher contrast than a
Katarina Cicak, Dale Li, Joshua Strong, Michael S. Allman, Fabio Altomare, Adam J. Sirois, Jed D. Whittaker, Raymond W. Simmonds
We have produced high quality resonant microwave circuits through developing a vacuum-gap technology for fabricating lumped-element capacitive and inductive components. We use micromachining to eliminate amorphous dielectric materials leaving vacuum in
This report summarizes the research and measurement science carried out during 2008-2009 in the NIST Physics Laboratory. The Laboratory supports U.S. industry, government, and the scientific community by providing measurement services and research for
Many perturbations that affect atomic frequency standards vary during the period of measurement. To include this time variation, we introduce three time-dependent weight functions built from the solution of the unperturbed equations of motion of a two
Air kerma calibration coefficients for a reference class ionization chamber from narrow x-ray spectra and cesium 137 gamma ray beams were compared between the National Institute of Standards and Technology (NIST) and the Kenya Bureau of Standards (KEBS). A
Robert D. Horansky, Greg Stiehl, James A. Beall, Kent D. Irwin, Alex Plionis, Michael W. Rabin, Joel N. Ullom
Atomic cascades caused by ions impinging on bulk materials have remained of interest to the scientific community since their discovery by Goldstein in 1902\cite{Sigmund}. While considerable effort has been spent describing and, more recently, simulating
Chin-Wen Chou, David Hume, J.C. Koelemeij, David J. Wineland, Till P. Rosenband
We have constructed an optical clock with a fractional frequency inaccuracy of 8.6e-18, based on quantum logic spectroscopy of an Al+ ion. A simultaneously trapped Mg+ ion serves to sympathetically laser-cool the Al+ ion and detect its quantum state. The
Zachary H. Levine, Jingyun Fan, Jun Chen, Alexander E. Ling, Alan L. Migdall
WWe analyze the generation of single spatial mode, spectrally uncorrelated photon pairs via type II spontaneous parametric downconversion in a Potassium Titanyl Phosphate (KTP) waveguide using real experimental parameters. We show that this source can be
Kevin J. Coakley, Jolene D. Splett, David S. Simons
We construct uncertainty intervals for weak Poisson signals in the presence of background. We consider the case where a primary experiment yields a realization of the signal plus background, and a second experiment yields a realization of the background
We present a small-signal wave propagation theory on matter-wave superradiant scattering. We show, in a longitudinally excited condensate, that the backward-propagating, superradiantly generated optical field propagates with ultraslow group velocity and
Ricardo Jimenez Martinez, William C. Griffith, Ying-ju Wang, Svenja A. Knappe, John E. Kitching, Ken Smith, Mark Prouty
We compare the sensitivity performance of two optically pumped atomic magnetometers based on the Mx and frequency-modulated Bell-Bloom configurations. The Cs magnetometers are implemented using a millimeter-scale microfabricated vapor cell in a
William H. Rippard, Alina M. Deac, Matthew R. Pufall, Justin M. Shaw, Mark W. Keller, Stephen E. Russek, Gerrit E. Bauer, Claudio Serpico
We have measured spin-transfer-induced dynamics in magnetic nanocontact devices having a perpendicularly magnetized Co/Ni free layer and an in-plane magnetized CoFe fixed layer. The frequencies and powers of the excitations agree well with the predictions
Li-Hong Xu, Jon T. Hougen, Jonathan M. Fisher, Ronald M. Lees
The aim of the present paper is to investigate the use of quantum chemistry calculations to obtain the torsional dependence of various structural and vibrational-force-field-related quantities that could help in estimating the vibration-torsion-rotation
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)
Michael Metcalfe, Andreas Muller, Glenn S. Solomon, John R. Lawall
We present a detailed study of the use of Fabry-Perot (FP) cavities for the spectroscopy of single InAs quantum dots (QDs). We derive optimal cavity characteristics and resolution limits, and measure photoluminescence linewidths as low as 0.9 GHz. By
A comparison has been made of the air-kerma standards for low-energy x-rays at the National Institute of Standards and Technology (NIST) and the Physikalisch-Technische Bundesanstalt (PTB). The comparison involved a series of measurements at the PTB and
Christopher G. Soares, Sameul Trichter, Slobodan Devic
Media that turns color upon being irradiated (coloration detectors) were some of the earliest available detectors for ionizing radiation. Besides conventional silver halide photographic media, which aided in the discovery of x-rays by Rontgen, barium
Joseph W. Britton, Ki W. Yoon, James A. Beall, Daniel T. Becker, Hsiao-Mei Cho, Gene C. Hilton, Michael D. Niemack, Kent D. Irwin
We are developing monolithic arrays of corrugated feed horns fabricated in silicon for dual-polarization single mode operation at 90, 145 and 220 GHz. The arrays consist of hundreds of platelet feed horns assembled from gold coated stacks of micromachined
A. V. Taichenachev, V. I. Yudin, Christopher W. Oates, Barber W. Zeb, Nathan D. Lemke, Andrew Ludlow, U Sterr, Ch. Lisdat, F Reihle
We develop a modified version of Ramsey spectroscopy that uses an additional frequency shift to compensate frequency shifts induced by the excitation itself. In its simplest realization, this method uses a small step of the probe frequency during the two