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William C. Griffith, Svenja A. Knappe, John E. Kitching, Ricardo Jimenez Martinez, Vishal Shah
High permeability magnetic flux concentrators are used to enhance the sensitivity of an atomic magnetometer operating in the spin exchange relaxation free regime. The magnetometer uses a millimeter scale 87Rb vapor cell and either mu-metal or Mn-Zn ferrite
A formidable array of advanced laser systems are emerging that produce extreme states of light and matter. By irradiating solid and gaseous targets with lasers of increasing energy densities, new physical regimes of radiation effects are being explored for
Kenneth G. Inn, Jerome LaRosa, Svetlana Nour, James J. Filliben, George Brooks, Stephen Lamont, Rob Steiner, Ross W. Williams, Brad Patton, Debbie Bostick, Gregory Eiden, Steve Petersen, Donna Beals, James Cadieux, Greg Hall, Steve Goldenberg, Stephen Vogt
For more than 20 years, countries and their agencies which monitor discharge sites and storage facilities have relied on the National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 4355 Peruvian Soil reference material. Its
This paper describes contributions to the workshop, 'Technology Development for a CMB Probe of Inflation,' held at NIST in Boulder CO, Aug. 25-28, 2008 concerning technologies to read out direct detectors (including bolometers and microwave kinetic
The Time and Frequency Bulleting provides information on performance of time scales and a variety of broadcasts (and related information) to users of the NIST services.
D. M. Rampulla, N Oncel, E Abelev, Y Yi, Svenja A. Knappe, S Bernasek
Coated atomic resonance cells are used in atomic magnetometers, atomic clocks, and magneto-optical traps. Recent work has shown that there is a significant difference in surface relaxation rates of spin-polarized alkali atoms on an OTS monolayer coating as
With a modulator based 10 GHz optical frequency comb generator at 1.55 mm, we report a 20 GHz repetitive train of optical pulses as short as 450 femtoseconds. The timing stability of the 20 GHz pulses, in addition to the power and phase for optical comb
High precision oscillators have significant applications in modern communication and navigation systems, radars, and sensors mounted in unmanned aerial vehicles, helicopters, missiles, and other dynamic platforms. These systems must provide their required
Ke Li, Lu Deng, Edward W. Hagley, M.S. Zhan, Marvin G. Payne
We demonstrate matter-wave self-imaging in a stationary light field in the non-Raman-Nath limit. We show that in a non-instantaneous pulsed standing wave grating significant contributions due to the non-negligible atomic center of mass motion and
Lawrence T. Hudson, A. Tommasini, A MacPhee, D. Hey, T Ma, C. Chen, N Izimi, W Unites, A. MacKinnon, P. Hatchett, B.A. Remington, H.S. Park, P. Springer, J. Koch, O.L. Landen, John F. Seely, G Holland
We present scaled demonstrations of backlighter sources, emitting Bremsstrahlung x rays with photon energies above 75 keV, that we will use to record x-ray Compton radiographic snapshots of cold dense DT fuel in inertial confinement fusion implosions at
I will discuss three methods of transmitting time and frequency information: one-way, two-way and common-view. I will describe the advantages and limitations of the different methods including ncertainty estimates for systems that are based on them.
We characterize the performance of GPS signals before, and after Architecture Evolution Plan (AEP) implementation. We use the period from May 20 through September 13, 2007, MJDs 54240-54356, as the period before AEP. The interval from September 14, 2007
Here I review a paper by Akatsuka et al. that appears in the current volume of Nature Physics. This work describes their latest experimental results on optical lattice clocks, including the first demonstration of a 3-D lattice clock.
This paper introduces a new device, a prototype common-view disciplined oscillator (CVDO) that can be locked to a remote time scale through the use of real-time common-view GPS measurements. A Proportional-Integral-Derivative (PID) controller is used to
Paul D. Kunz, Thomas P. Heavner, Steven R. Jefferts
We are developing a simple and transportable laser-cooled rubidium (Rb) atomic fountain frequency standard. The optical package for this system uses DFB (distributed feedback) diode lasers and a frequency offset locking scheme to generate the optical
This paper covers the current status and future plans of the modernized LORAN systems in North America, the European Union, Asia, & Saudi Arabia. Special focus is placed on the enhanced LORAN system in North America and Europe. These modernized systems
A time scale is a procedure for combining the data from an ensemble of clocks or frequency standards. The input data to the ensemble algorithm are generally the time (or frequency) differences between each of the members and the reference device for the
Michael A. Lombardi, Andrew N. Novick, Jose M. Lopez, Francisco Jimenez, Jean-Simon Boulanger, Raymond Pelletier, Ricardo de Carvalho, Raul Solis, Carlos Donado, Harold Sanchez, Carlos A. Quevedo, Gregory Pascoe, Daniel Perez
The Sistema Interamericano de Metrologia (SIM) consists of national metrology institutes (NMIs) located in the 34 member nations of the Organization of American States (OAS), which extends throughout North, Central, and South America, and the Caribbean
The National Institute of Standards and Technology (NIST) maintains one of the world s most accurate and stable time scales, and also developed and maintains the primary frequency standard for the United States. Various techniques are used to compare the
Jennifer A. Taylor, Craig W. Nelson, Archita Hati, Neil Ashby, David A. Howe
Oscillators operating in field applications are subject to much more strenuous environmental effects than those in the laboratory. These environmental effects, like vibration and temperature fluctuation, have a great impact on the performance of the
Nathan D. Lemke, Andrew Ludlow, Zeb Barber, N Poli, C.W. Hoyt, Long-Sheng Ma, Jason Stalnaker, Christopher W. Oates, Leo Hollberg, James C. Bergquist, A. Brusch, Tara Fortier, Scott Diddams, Thomas P. Heavner, Steven R. Jefferts, Tom Parker
We describe the development and latest results of an optical lattice clock based on neutral Yb atoms, including investigations based on both even and odd isotopes. We report a fractional frequency uncertainty below 10 -15 for 171Yb.
Jeffrey S. Kline, Haohua Wang, Seongshik Oh, John M. Martinis, David P. Pappas
We have found that crystalline Josephson junctions have critical current density control problems which decrease circuit yield. We present a qubit circuit designed to accommodate a factor-of-five variation in critical current density for the evaluation of
Archita Hati, Craig W. Nelson, Jennifer A. Taylor, David A. Howe
Vibration causes mechanical distortions in fiber-optic transmission lines that induce phase fluctuations. A scheme is described which enables electronic cancellation of vibration-induced phase noise in an optical fiber wound on a spool. We report 20 dB or
Lawrence T. Hudson, H.S. Parks, B.R. Maddox, E. Giraldez, P. Hatchett, N. Izumi, M.H. Key, S. LePape, A. MacKinnon, A MacPhee, P.K. Patel, T.W. Phillips, B.A. Remington, John F. Seely, A. Tommasini, R. Town, J. Workman
We have developed 17 keV to 75 keV 1-dimensional and 2-dimensional high-resolution (<10 m) radiography using high-intensity short pulse lasers. High energy K- sources are created by fluorescence from hot electrons interacting in the target material after