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Search Publications

NIST Authors in Bold

Displaying 16826 - 16850 of 74137

Superexchange mediated magnetization dynamics in a 2D checkerboard optical lattice

May 1, 2015
Author(s)
Elizabeth A. Goldschmidt, Roger C. Brown, Silvio B. Koller, Michael S. Foss-Feig, James V. Porto, Robert Wyllie
The interplay of spin and motion underlies some of the most intriguing and poorly understood behaviors in many-body quantum systems. A well known example is the onset of superconductivity in cuprate compounds when mobile holes are introduced into an

Tap On, Tap Off: Onscreen Keyboards and Mobile Password Entry

May 1, 2015
Author(s)
Kristen Greene, Joshua M. Franklin, John M. Kelsey
Password entry on mobile devices significantly impacts both usability and security, but there is a dearth of usable security research in this area, specifically for complex password entry. To address this research gap, we set out to assign strength metrics

Terbium-Doped Magnetite Nanocrystals for Multimodal Imaging Agents

May 1, 2015
Author(s)
Katherine P. Rice, Stephen E. Russek, Roy H. Geiss, Justin M. Shaw, Robert J. Usselman, Eric R. Evarts, Thomas J. Silva, Hans T. Nembach, Elke Arenholz, Yves Idzerda
High quality cubic Tb-doped magnetite nanocrystals have been fabricated and have shown that the Tb is incorporated into the octahedral 3+ sites. Magnetization and FMR data indicate that the Tb spins are weakly coupled to the iron spin lattice at room

Two determinations of the 223Ra half-life

May 1, 2015
Author(s)
Denis E. Bergeron, Ryan P. Fitzgerald
Ra-223 is an alpha-emitter that is being used as a bone-seeking radiotherapeutic agent. The relatively large uncertainty on its half-life (0.26 %, Bé et al., 2011) is an impediment to precision activity assays. We have performed two series of measurements

A Compact Millimeter-wave Multisine Generator for Calibrating Broadband Vector Receivers

April 30, 2015
Author(s)
Paul D. Hale, Kate Remley, Dylan Williams, Jeffrey Jargon, Chih-Ming Wang
We propose a compact and low cost waveform source that can be used to calibrate the magnitude and phase response of vector receivers over a bandwidth as large as a few gigahertz. The generator consists of a broadband comb generator followed by a filter and

Interactions of Higher Order Tip Effects in CD-AFM Linewidth Metrology

April 30, 2015
Author(s)
Ronald G. Dixson, Boon Ping Ng, Xavier Bonnaud, Ndubuisi G. Orji
A major challenge in critical dimension atomic force microscope (CD-AFM) width metrology is accounting for the effects of the tip on the apparent features in an image. The overall effect of the tip is to broaden the apparent width of lines and narrow the

Validated Open Source Nanofiber Diameter Measurement Tool

April 30, 2015
Author(s)
Nathan A. Hotaling, Kapil Bharti, Haydn Kriel, Carl G. Simon Jr.
Despite the growing use of nanofiber scaffolds for tissue engineering applications, there is not a validated, readily available (commercial or open source) solution for rapid, automated analysis of nanofiber diameter from scanning electron microscope (SEM)

Chemically-Sensitive Bioimaging with Coherent Raman Scattering

April 29, 2015
Author(s)
Charles H. Camp, Marcus T. Cicerone
Raman scattering provides an intrinsic fingerprint of chemical composition. Spontaneous Raman spectroscopy has been used for many decades to interrogate biological materials and systems, but is not widely used for imaging due to relatively slow signal

Post-process machining of additive manufactured stainless steel

April 29, 2015
Author(s)
Brandon M. Lane, Shawn P. Moylan, Eric P. Whitenton
Due to the poorer surface finish and geometric accuracy of additive manufactured (AM) parts compared to machined parts, it is inevitable that parts fabricated through AM processes will require post-process machining. This problem was identified early by

Progress Toward Standardized Additive Manufacturing Test Artifacts

April 29, 2015
Author(s)
Shawn P. Moylan
Users and buyers of additive manufacturing (AM) systems need to know system performance characteristics to make important, basic decisions such as whether or not the system is capable of manufacturing their parts. Unfortunately, there are no standard

Separation of Magnetic and Superconducting Behaviour in YBa 2 Cu 3 O 6.33 (T c =8.4 K)

April 29, 2015
Author(s)
Zahra Yamani, W.J. L. Buyers, F Wang, Young-June Kim, Jae-Ho Chung, Sung Chang, Peter M. Gehring, Goran Gasparovic, Christopher Stock, C. L. Broholm, J.C. Baglo, Ruixing Liang, D. A. Bonn, W. N. Hardy
Neutron scattering from high-quality YBa2Cu3O6.33 (YBCO6.33) single crystals with a Tc of 8.4 K shows no evidence of a coexistence of superconductivity with long-range antiferromagnetic order at this very low, near-critical doping of p0.055. However, we

Data-Driven Decision-Making: Using Bibliometrics for Collection Analysis

April 28, 2015
Author(s)
Stacy M. Bruss
You may be familiar with using bibliometrics, the quantitative analysis of scholarly literature, to assess the impact of researchers. But have you used it to assess the impact of your collection and to perform evidence-based collection development? Bruss

Near-infrared single-photon spectroscopy of a whispering gallery mode resonator using energy-resolving transition edge sensors

April 28, 2015
Author(s)
Thomas Gerrits, Michael Fortsch, Martin J. Stevens, Dmitry Strekalov, Gerhard Schunk, Josef Furst, Ulrich Vogl, Florian Sedlmeir, Harald G. Schwefel, Gerd Leuchs, Christoph Marquardt
We demonstrate a method to perform spectroscopy of near-infrared single photons without the need of dispersive elements. This method is based on a photon energy resolving transition edge sensor and is applied for the characterization of a widely wavelength
Displaying 16826 - 16850 of 74137