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V. Madic, W. Rau, D. S. Akerib, P. Brink, B. Cabrera, J. P. Castle, Fengbo Hang, M. B. Crisler, D. Driscoll, J. Emes, R. J. Gaitskell, J. Hellmig, Martin Huber, S. Kamat, John M. Martinis, P. Meunier, T. A. Perera, M. Perillo-Issac, T. Saab, B. Sadoulet, R. W. Schnee, D. N. Seitz, G. Wang, B. A. Young
The Ge and Si detectors developed by the Cryogenic Dark Matter Search (CDMS) II experiment rely on the simultaneous detection of athermal phonons and ionization produced by interactions in the crystal. The athermal phonons provide both the total energy
This book describes the programs in the Radio-Frequency Technology Division, of the National Institute of Standards and Technology. The Radio-Frequency Technology Division is a critical national resource for a wide range of customers. U. S. industry is the
B. Cabrera, John M. Martinis, Aaron J. Miller, Sae Woo Nam, R. W. Romani
We describe our recent progress on superconducting transition-edge sensor (TES) spectrophotometers in the spectral range from the near infrared through ultraviolet bands. These instruments time-stamp (0.1 υs) and energy-resolve (0.15 eV FWHM) each photon
Najib Cheggour, John (Jack) W. Ekin, Cameron C. Clickner, Ron Feenstra, P Goyal, D F. Paranthaman, D F. Lee, D M. Kroeger, D. K. Christen
The electromechanical properties of (0.3 υm thick) yttrium-barium-copper-oxide (YBCO) coatings on buffered pure-nickel rolling-assisted-biaxially-textured substrates (RABiTS) were measured at 76 K and self magnetic field. YBCO coatings on buffered
We have investigated the mutual inductance observed on pairs of voltage tapes that are soldered to superconducting wires in order to measure the voltage-current (V-I) characteristics & determine the critical current. Measurements on a Nb-Ti superconductor
The Magnetic Technology Division develops and disseminates unique measurement technology for industries concerned with magnetic information storage and superconductor power. The division's projects are led by senior scientists, often assisted by engineers
We present results for uncertainties in noise-parameter measurements, obtained using a Monte Carlo simulation of the measurements. Sets of data were generated to simulate measurements on a low-noise amplifier, with given uncertainties in the underlying
A microcalorimeter and bolometer transfer standard are used as a national standard for microwave power from 50 MHz to 50 GHz. the microcalorimeter is used to determine the efficiency of the bolometric transfer standards and is similar to an existing Type N
The increase in processor speeds in the last few years has created a growing need for the accurate characterization of waveform propagation on lossy printed circuit board (PCB) transmission lines. In 1980, Gumerova, Efimov and Kostenko introduced an
This paper compares closed-form approximations for coplanar waveguide and microstrip transmission-line parameters to accurate measurements and full-wave calculations. We suggest improved approximations and demonstrate the limitations of our proposed and
This paper is an overview on the RF materials characterization metrology at NBS/NIST. Over the years, measurements on the electrical permittivity and permeability as functions of frequency and temperature have been crucial for a wide array of applications
The phase diagram for the orientation of the surface region is calculated in the parameter space defined by the surface and bulk anisotropy in semi-infinite ferromagnetic systems and in thin ferromagnet films. Surface magnetic canting always occurs when
The economic development of the Twentieth Century was accompanied and enhanced by the increasing use of documentary standards, largely developed by industry. In the current environment, companies and nations in global competition adopt various strategies
Claude Weil, David R. Novotny, Robert T. Johnk, Arthur Ondrejka
We discuss progress in developing a new broadband (10MHz to 40MHz) RF field standard to be used for calibrating small electromagnetic field probes. The technique generates a well-defined and uniform TEM mode field between the conductors of an air-filled
Richard G. Geyer, Pavel Kabos, James R. Baker-Jarvis
Closed-form analytical solutions are derived for accurate microwave dielectric characterization of rod test specimens inserted into dielectric sleeve resonators placed certrally in a metal cavity. Low-loss sleeve resonators can be used advantageously for
New engineered artificial and metamaterials combine ferroelectrics, ferrites, wires, resonant rings, and ferromagnetic materials to obtain a desired response. In this paper we develop constitute relations for materials where the magnetization and
I address the issue of the definition and measurement of noise figure and parameters to characterize multiport devices, particularly differential amplifiers. A parameterization in terms of the noise matrix appears to be the most practical. the noise figure
Although the theory is straightforward, practical implementation of spherical near-field scanning for evaluating test chambers presents some significant challenges. Among these are the requirement for accurate probe positioning and the difficulty in
David R. Novotny, Robert T. Johnk, Claude Weil, Seturnino Canales
We have developed a methodology to determine the quality of an EMC test facility using equipment that may be generally available to RF testing services. By utilizing both, the time- and frequency-domains, an accurate picture of the scattering , and modal
A new measurement and analysis technique to isolate the background signals present in radar cross section measurements is presented. By definition the measured RCS of a target is independent of the measured phase, but it is not independent of the phase
We describe micro cantilevers developed for in-situ measurements of ultra-thin ferromagnetic films. The cantilevers are optimized for use in a resonating torque micro-balance magnetometer that measures the magnetic moment of thin films as they are being
Alpesh Bhobe, Christopher L. Holloway, Melinda Piket-May
Full wave finite-difference time-domain (FDTD) and a simplified 1D- finite-difference time-domain technique using the multi-conductor transmission line equations are applied to a delay line to determine its propagation characteristics. The output volatge
David R. Novotny, Robert T. Johnk, Arthur Ondrejka
We present and analyze a method for free-field evaluation of broadband absorber in a non-ideal testing environment. Using broadband, short-impulse TEM horns, a frequency-rich spectrum (equivalent pulse length 0.5 ns) illuminates a sample of the material
Robert T. Johnk, David R. Novotny, Claude Weil, Marlene Taylor, T. J. O'Hara
This paper summarizes a joint NIST-Industry measurement effort. The purpose of this effort was to use a NIST-developed ultrawideband measurement system to assess the performance improvement of ferrite tile anechoic chamber after a partial retrofit