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Polymer-derived SiCN composites with magnetic properties

November 1, 2003

Author(s)

Atanu Saha, Sandeep R. Shah, Rishi Raj, Stephen E. Russek

Composites consisting of particles of α-iron dispersed in silicon carbonitride (SiCN) were fabricated by a polymer route. The composites had iron inclusions with the same magnetization as bulk iron, but they resisted oxidation up to 500°C and had a

Broadband impedance parameters of assymetric coupled CMOS interconnects: new closed-form expressions and comparison with measurements

October 29, 2003

Author(s)

Amy Luoh, Uwe Arz, Hartmut Grabinski, Dylan Williams, Dave K. Walker, Andreas Weisshaar

New broadband closed-form expressions for the frequency-dependent impedance parameters of asymmetric coupled coplanar interconnects on a conductive silicon substrate are developed. The closed-form expressions are based on a complex image approach to

A Modified Approach to de Broglie Wave Mechanics in Applied Electromagnetic Fields

October 21, 2003

Author(s)

James R. Baker-Jarvis, Pavel Kabos

The goal of this paper is to reformulate the de Broglie-Bohm model of wave mechanics with applied electromagnetic fields. The Schroedinger and Klein-Gordon equations are separated into component equations for classical action and a linear self-interaction

IEEE Standard 802.16 for Global Broadband Wireless Access

October 21, 2003

Author(s)

Roger Marks

Global standardization is a key issue for the success of broadband wireless access systems. The IEEE 802.16 Working Group on Broadband Wireless Access, with hundreds of participants worldwide, has developed IEEE Standard 802.16, with its WirelessMAN air

Phase-Dependent RCS Measurements in the Presence of Outliers

October 19, 2003

Author(s)

Lorant A. Muth, Timothy Conn

Coherent radar cross section measurements on a target moving along the line-of-sight in free space will trace a circle centered on the origin of the complex (I,Q) plane. The presence of additional complex signals (for example, background, clutter, average

Radiometer Phase Retardation Plate Evaluation Using Planar Near-field Antenna Measurements

October 19, 2003

Author(s)

Jeffrey R. Guerrieri, Katherine MacReynolds, Douglas T. Tamura

The National Institute of Standards and Technology (NIST) characterized three phase retardation plates for the National Oceanic & Atmospheric Administration (NOAA). These plates are used to produce known polarized signals needed to calibrate polarimetric

Uncertainty Analysis for Spherical Near-Field Measurement

October 19, 2003

Author(s)

Michael H. Francis, Ronald C. Wittmann

A general approach is introduced for estimating uncertainties in far-field paramenters from spherical near-field measurements. Although the analysis is incomplete at present, we expect that as the measurement radius increases, our results will transform

Uncertainty Analysis of RCS Calibrations at the Etcheron Valley Range

October 19, 2003

Author(s)

Lorant A. Muth, Dale M. Diamond, John Liles, James Adams

We have been developing the uncertainty analysis of RCS calibrations and measurements at the Etcheron Valley RCS outdoor ground-bounce facility in the 2-18 GHz range. In this study we report on the results of the uncertainty analysis primarily at 11.3 GHz

RF and IF mixer optimum matching impedances extracted by large-signal vectorial measurements

October 7, 2003

Author(s)

Alessandro Cidronali, Giovanni Loglio, Jeffrey Jargon, Kate Remley, I. Magrini, Donald C. DeGroot, Dominique Schreurs, Kuldip Gupta, Gianfranco Manes

This paper introduces a new technique that allows us to measure the admittance conversion matrix of a two-port device, using a Nonlinear Vector Network Analyzer. This method is applied to extract the conversion matrix of a 0.2 micron pHEMT, driven by a 4.8

RF Behavioural Modelling from Multisine Measurements: Influence of Excitation Type

October 7, 2003

Author(s)

Dominique Schreurs, M. Myslinski, Catherine A. Remley

Behavioural models for RF devices are typically based on large-signal RF measurements. Until now, those measurements were usually limited to single-tone excitations. In this work, we focus on the use of multisines in the experiment design, and, more

Averaged Transition Conditions for Electromagnetic Fields at a Metafilm

October 1, 2003

Author(s)

Edward Kuester, Mohamed Mohamed, Christopher L. Holloway, Melinda Picket-May

This work derives generalized sheettransition conditions (GSTCs) for the average electromagnetic fields across a surface distribution of electrically small scatterers characterized by electric and magnetic polarization densities. We cann such an

Local and Macroscopic Electromagnetic Fields Using Projection-Operator Based Statistical Mechanics

October 1, 2003

Author(s)

James R. Baker-Jarvis

I study the origins of the applied, macroscopic, and local electromagnetic fields by a statistical-mechanical method. In order to obtain the macroscopic fields from the microscopic fields we use a relevant statistical-density function for ensemble

High-Frequency Characteristics of Metal/Native-Oxide Multilayers

September 5, 2003

Author(s)

Geoffrey S. Beach, Thomas J. Silva, F. T. Parker, A. E. Berkowitz

The high-frequency magnetization dynamics of magnetically soft Co χFe 100-χ metal/native-oxide multilayers were studied as a function of alloy composition (10 less than or equal to} χ less than or equal to} 50) using a time-domain inductive technique. The

Induced Currents on an EUT in a Free-Space and a Modified TEM Cell Environment

August 19, 2003

Author(s)

Per E. Fornberg, Christopher L. Holloway, Perry F. Wilson

The finite-difference time-domain method is used to investigate whether the currents induced on an equipment under test (EUT) in a TEM cell are similar to those induced in an ideal free-space environment. The approach is to simulate an identical EUT in

Assessing A Loaded Reverberation Chamber: Calculating Threshold Metrics

August 18, 2003

Author(s)

Christopher L. Holloway, David A. Hill, John M. Ladbury, Todd M. Lammers

In this paper we present an expression for two threshold metrics of a loaded reverberation chamber. One metric is based on the chamber quality factor (Q) and the other is based on a useable volume of a loaded reverberation chamber. These metrics are

Total Radiated Power Limits for Emission Measurements in a Reverberation Chamber

August 18, 2003

Author(s)

Christopher L. Holloway, Perry F. Wilson, Galen H. Koepke, Marco Candidi

In this paper we present a total radiated power limit for emission measurements in reverberation chambers. This total radiation power limit is intended to be equivalent to the FCC maximum E-field limit for emission testing over a ground plane.

The impact of internal sampling circuitry on the phase error of the nose-to-nose oscilloscope calibration

August 1, 2003

Author(s)

Catherine A. Remley

We study the dependence of the phase error in the nose-to-nose oscilloscope calibration on the oscilloscope's internal sampling circuitry. We first develop a robust sampling-circuit model for use in numerical simulations of the nose-to-nose derived

Materials dependence of the spin-momentum transfer efficiency and critical current in ferromagnetic metal/Cu multilayers

July 14, 2003

Author(s)

Matthew Pufall, William Rippard, Thomas J. Silva

We have quantitatively compared spin momentum transfer effects in FM/Cu multilayers, with FM = Co, Co 90Fe 10, Ni 80Fe 20, Ni 40Fe 10Cu 50, and Fe. All of the measured multilayers exhibited an abrupt step in the resistance at a critical current I c, the

EMC Research at NIST, Boulder

July 11, 2003

Author(s)

Perry F. Wilson, Christopher L. Holloway, Galen H. Koepke, John M. Ladbury, Arthur Ondrejka, Robert T. Johnk, Keith D. Masterson, Dennis G. Camell

N/A

Dielectric Characterization of Ferroelectric Ceramics with Sleeve Resonator Techniques at Microwave Frequencies

July 8, 2003

Author(s)

Richard G. Geyer, Pavel Kabos, James R. Baker-Jarvis

Temperature-stable, high-Q sleeve resonators may be used for variable temperature dielectric characterization of rod-shaped ferroelectric test specimens at microwave frequencies. The nominal measurement frequency is determined by the permittivity and

Variation of the effective magnetization and the Lande g factor with thickness in thin Permalloy films

July 7, 2003

Author(s)

John P. Nibarger, Radek Lopusnik, Thomas J. Silva, Zbigniew J. Celinski

We have simultaneously measured the Lande g factor, the effective magnetization, M eff, and the uniaxial anisotropy, H k, and the Gilbert damping parameter α, as a function of Permalloy film thickness from 2.5 to 50 nm. We used a pulsed inductive microwave

Different Dynamic and Static Magnetic Anisotropy in Thin Permalloy Films

July 6, 2003

Author(s)

Radek Lopusnik, John P. Nibarger, Thomas J. Silva, Zbigniew J. Celinski

The values of uniaxial anisotropy Hk in thin polycrystalline Permalloy films measured by static and dynamic methods differ by as much as a factor 1.5. The anisotropy obtained with a pulsed inductive microwave magnetometer in 2.5-100 nm thick Permalloy

High-frequency noise measurements in spin-valve Devices

July 1, 2003

Author(s)

N. A. Stutzke, S. L. Burkett, Stephen E. Russek

High-frequency magnetic noise in magnetoresistive devices being developed for read-sensor and magnetic random access memory applications may present fundamental limitations on the performance of sub-micrometer magnetic devices. High- frequency magnetic

In-situ conductance characterization of Fe/Ag multilayer contacts on GaAs

July 1, 2003

Author(s)

Dustin Hite, Stephen E. Russek, David P. Pappas

Electrical transport characteristics for epitaxially grown Ag/Fe/Ag multilayers on GaAs(100) and GaAs(110) have been studied under various growth conditions. The surfaces and structure of the multilayer were characterized by low energy electron diffraction

Measurement Techniques and Results of an Intercomparison of Horn Antenna Gain in IEC-R 320 at Frequencies of 26.5, 33.0 and 40.0 GHz

July 1, 2003

Author(s)

David Gentle, A. Beardmore, J. Achkar, J Park, Katherine MacReynolds, Jan P. deVreede

A measurement comparison of the boresight gain of two IEC-R320 horn antennas has been carried out between five national metrology laboratories at 26.5, 33 and 40 GHz. The following five national metrology laboratories participated: NPL (United Kingdom)