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Thomas Gerrits, Thomas J. Silva, Hugo A. van den Berg, Theo Rasing
We present a method for simultaneous measuring the two normalized in-plane magnetization components in magnetic thin films that allows for the reconstruction of the magnetization angle and the normalized value of the magnetization with subnanosecond
Thomas Gerrits, Michael Schneider, Anthony B. Kos, Thomas J. Silva
A time-resolved ferromagnetic resonance technique was used to investigate the nonlinear magnetization dynamics of a 10 nm thin Permalloy TM film in response to a sequence of large-amplitude field pulses. The magnetic field pulse sequence was set at a
Catherine A. Remley, Marc Rutschlin, Dylan F. Williams, Robert T. Johnk, Galen H. Koepke, Christopher L. Holloway, Mike G. Worrell, Andy MacFarlane
To assess in-building radio coverage, in 2004 the City of Phoenix Fire Department carried out extensive testing of their radio systems. They deployed firefighters in standard configurations in a variety of buildings, and rated on a scale of 1 to 5 the
A direct comparison power measurement system has been developed to measure power sensor effective efficiency in the 100 kHz to 18 GHz frequency range. This system is capable of measuring thermistor and thermoelectric based power sensors. Several problems
James P. Randa, Eyal Gerecht, Dazhen Gu, Robert L. Billinger
We report precision measurements of the effective input noise temperature of a cryogenic (liquid helium temperature) MMIC amplifier at the amplifier reference planes within the cryostat. A method is given for characterizing and removing the effect of the
M H. Park, Y K. Hong, B C. Choi, S H. Gee, Michael J. Donahue
Magnetization configuration of vortex head-to-head (HTH) domain walls and the wall formation process in Ni80Fe20 ring elements were investigated using magnetic force microscopy and micromagnetic simulation. At remanence, two types of vortex HTH domain
Charles Dietlein, A. Luukanen, Francois Meyer, Zoya Popovic, Erich N. Grossman
Images acquired by a 105-mK noise equivalent temperature difference (NETD) scanned single-pixel broadband 0.1-1 THz passive system are analyzed with two specific parameters of interest in mind. First, the minimum system noise level for clothing feature
We describe a novel class of millimeter-wave and terahertz monochrometers based on adiabatically tuned frequency-selective surfaces. They are analogous to the circular-variable filters commonly used in the infrared for low to moderate resolution
Christopher L. Holloway, David A. Hill, Galen H. Koepke, John M. Ladbury
In this paper we present two versions of a threshold metric for the purpose of accessing the effectiveness of a reverberation chamber. One metric is based on the chamber quality factor (Q), and the other is based on the volume of the loaded reverberation
M. R. Fitzsimmons, Thomas J. Silva, T. M. Crawford
The chemical and magnetic structures of oxides on the surface of Permalloy Ni 81Fe 19 films were investigated as functions of annealing time with x-ray and polarized neutron reflectometry. For annealing times of less than one hour, the oxide consisted of a
Thomas Gerrits, Michael Schneider, Thomas J. Silva
We have investigated the enhancement of ferromagnetic damping for thin Permalloy (Ni 80Fe 20) films grown with Cu capping layers of variable thickness (5-1000nm). The measurements were performed with a pulsed inductive microwave magnetometer in the
Daniel C. van der Laan, John (Jack) W. Ekin, Hans J. van Eck, M Dhalle, Bennie ten Haken, Michael W. Davidson, Justin Schwartz
The grain-to-grain connectivity in Bi 2Sr 2Ca 2Cu 3O x tapes is still poorly understood, even though they have been commercially available in long lengths for several years. This letter explains the effects of tensile strain on the grain-to-grain
Cameron C. Clickner, John (Jack) W. Ekin, Najib Cheggour, C. L. H. Thieme, You-Lin Qiao, Y Y. Xie, P Goyal
Mechanical properties of rolling-assisted, biaxially-textured substrates (RABiTS) and substrates for ion-beam assisted deposition (IBAD) coated superconductors are measured at room temperature, 76, and 4 K. Yield strength, Young's modulus, and the
Dylan F. Williams, Arkadiusz C. Lewandowski, Tracy S. Clement, C. M. Wang, Paul D. Hale, Juanita M. Morgan, Darryl A. Keenan, Andrew Dienstfrey
We develop a covariance matrix describing the uncertainty of mismatch-corrected measurements performed on the National Institute of Standards and Technology's electro-optic sampling system. This description offers a general way of describing the
Mark Hoefer, Mark J. Ablowitz, Boaz Ilan, Matthew Pufall, Thomas J. Silva
A nonlinear model of spin-wave excitation using a point contact in a thin ferromagnetic film is introduced. Large-amplitude magnetic solitary waves are computed, which help explain recent spin-torque experiments. Numerical simulations of the fully
Alexander J. Barker, Brant Cage, Stephen E. Russek, Ruchira Garg, R Shandas, Conrad Stoldt
Two potential molecular imaging vectors are investigated for material properties and magnetic resonance imaging (MRI) contrast improvement. Monodisperse magnetite (Fe 3O 4) nanocrystals ranging in size from 7 to 22 nm are solvothermally synthesized by
Roberto Bonin, Michael Schneider, Thomas J. Silva, John P. Nibarger
We present a quantitative, systematic study of the effect of magnetostriction on the dynamical properties in NiFe alloys. Both the ferromagnetic resonance frequency and the damping times are correlated to the magnetostriction. In addition, we find that the
As nanoscale electromagnetic measurements become more common, it is important for the understanding of microstructural electromagnetic interactions to keep pace. The use of time-dependent entropy in the analysis and measurement metrology of electromagnetic
Najib Cheggour, John (Jack) W. Ekin, Y Y. Xie, V Selvamanickam, C. L. H. Thieme, D. T. Verebelyi
A Cu protection layer added to yttrium-barium-copper-oxide (YBCO) coated conductors substantially enhances the irreversible strain limit Ε irr for the onset of permanent electrical damage of the composite. This enhancement is of significance since it
John Kitching, Svenja A. Knappe, Li-Anne Liew, John M. Moreland, Hugh Robinson, Peter D. Schwindt, V Shah, V Gerginov, Leo W. Hollberg
The physics package for a chip-scale atomic frequency reference was constructed and tested. The device has a total volume of 9.5 mm 3, dissipates 75 mW of electrical power at an ambient temperature of 45 °C and has a short-term fractional frequency
James P. Randa, Susan L. Sweeney, Tom McKay, Dave K. Walker, David R. Greenberg, Jon Tao, Judah Mendez, G. Ali Rezvani, John J. Pekarik
We present results of an interlaboratory comparison of S-parameter and noise-parameter measurements performed on 0.12 υm gate-length CMOS transistors. Copies of the same device were measured at three different laboratories (IBM, NIST, RFMD), and the
Coherent radar cross section measurements on a target moving along the system 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 background signals (including stationary