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Billy F. Riddle, James R. Baker-Jarvis, Jerzy Krupka
In this paper we present complex permittivity data at macorwave frequencies for many common plastics from 125 K to 375 K. The measurements were made using a TE 01δ dielectric resonator placed inside an environmental chamber. Data are presented for the
Kevin Coakley, Jolene Splett, Michael D. Janezic, Raian K. Kaiser
We estimate the quality factor Q and resonant frequency f 0 of a microwave cavity based on resonance curve observations on an equally-spaced frequency grid. The observed resonance curve is the squared magnitude of an observed complex scattering parameter
A potential low magnetic moment standard reference material (SRM) was studied in an interlaboratory comparison. The mean and the standard deviation of the saturation moment m s, the remanent moment m r, and the intrinsic coercivity H c of nine samples were
This is a summary of recent efforts conducted under the auspices of the American National Standards Institute (ANSI) Accredited Standards Committee C63, Sub-committee 1, working group 1-13.2. The main purpose of this group is to assess the applicability of
Orhan Kizilkaya, Dustin Hite, David M. Zehner, Phillip T. Sprunger
The surface morphology and atomic structure of clean and oxidized FeAl(l 10) surfaces have been investigated with scanning tunneling microscopy (STM). An incommensurate reconstructed structure, having FeAl2 stoichiometry confined to the outmost layer, is
Pavel Kabos, Howard C. Reader, Uwe Arz, Dylan Williams
We develop an on-wafer waveform calibration technique that combines frequency-domain mismatch corrections to account for the effects of the probe on the measurement with an oscilloscope calibration. The mismatch correction is general and can be applied to
High-frequency noise of micrometer-dimension spin valve devices has been measured as a function of applied field and temperature. The data are well fit with single-domain noise models that predict that the noise power is proportional to the imaginary part
Chriss A. Grosvenor, Robert T. Johnk, David R. Novotny, Seturnino Canales, Claude Weil, Jason Veneman
The National Institute of Standards and Technology participated in a comprehensive study of electromagnetic aircraft shielding. The effort consisted of two parts: (1) shielding measurements on a box model with a simple and precisely controlled geometry
Z. Y. Liu, P. A. Dowben, A P. Popov, David P. Pappas
Gadolinium occurs, in natural abundance, as several isotopes. The possible combinations of different gadolinium isotopes dictates that even for a fixed number of atoms in the cluster, clusters of gadolinium atoms will exhibit a range of masses. This and
Najib Cheggour, John (Jack) W. Ekin, Cameron C. Clickner, Ron Feenstra, P Goyal, D F. Paranthaman, Noel Rutter
Transport properties of yttrium-barium-copper-oxide (YBCO) coatings on both pure-nickel and nickel-3at%tungsten rolling-assisted-biaxially-textured substrates (RABiTS) were tested under transverse compressive stress up to 180 MPa. Transport critical
Stephen E. Russek, Shehzaad F. Kaka, Robert McMichael, Michael J. Donahue
The intent of this chapter is to review high frequency magnetic device measurements and modeling work at NIST which is being conducted to support the development of high-speed read sensors, magnetic random access memory, and magnetoelectronic applications
I review some of the novel methods for measuring ferromagnetic properties of thin films based on micromechanical magnetometers. Measurements rely on the detection of mechanical forces or torques on samples deposited onto microcantilevers. Displacements of
The influence of Mg doping on the structure, microstructure, surface morphological and dielectric properties of Ba1-xSrxTiO3 (BST) thin films has been measured and analyzed. The films were fabricated on MgO substrates with the metalorganic solution
Michael D. Janezic, Dylan Williams, V. Blaschke, A. Karamcheti, Fengbo Hang
We develop a broadband technique for measuring the permittivity of low-k thin films using microstrip transmission-line measurements. From measurements of the complex microstrip propagation constant and the characteristics impedance, we determine the
This publication 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
Scanning tunneling microscopy (STM) and photoelectron spectroscopy (PES) have been used to investigate the nucleation, growth, and structure of beryllium on Si(1 1 1)-(7 x 7). STM indicates that a chemical reaction occurs at temperatures as low as 120 K
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 generally available to RF testing services. By utilizing both the time- and frequency-domain, an accurate picture of the scattering and modal properties of the
The Magnetic Technology Division develops and disseminates measurement technology for industries broadly concerned with magnetic information storage and superconductor power. The division is located in Boulder, Colorado, part of the Electronics and
We use simulations to study the dependence of the phase error in the nose-to-nose oscilloscope calibration on the oscilloscope's sampling circuitry. We determine which components of the internal sampling circuitry of the oscilloscope contribute most
Jeffrey Jargon, Donald C. DeGroot, Kuldip Gupta, Alessandro Cidronali
We describe a method for preserving time-invariant phase relationships when ratios are taken between any two harmonically-related, complex signals. We provide a simple example to illustrate our technique, and show hot this method is implemented when
The calibration of nonreciprocal radars has been studied extensively. Here we present a robust calibration procedure using Fourier analysis of back-scatter data from a rotating dihedral. We derive a set of nonlinear equations in terms of the Fourier
Free space coherent radar cross section measurements on a moving target will trace a circle centered on the origin of the complex (I,Q) plane. Noise will introduce only small random variations in the radius of the circle. In real measurement configurations
Allen C. Newell, Jeffrey R. Guerrieri, Katherine MacReynolds
This paper describes two methods that can be used to measure the leakage signals, predict the effect on the far-field pattern and correct the measured data for leakage bias errors without additional near-field measurements. One method is an extension and
Ronald C. Wittmann, Bradley Alpert, Michael H. Francis
We introduce a near-field spherical scanning algorithm that relaxes the usual condition requiring data points to be on a regular spherical grid. Computational complexity is of the same order as for the standard (ideal-positioning) spherical-scanning
Ronald C. Wittmann, Carl F. Stubenrauch, Michael H. Francis
We discuss the mitigation of truncation errors in spherical scanning measurement. The main emphasis is the spherical harmonic representation of probe transmitting and receiving functions; however, our method is applicable to near-field measurement of