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NIST Authors in Bold

Displaying 29701 - 29725 of 74129

Calibration of a Force Feedback Joystick

August 29, 2008
Author(s)
J H. Daruwalla, Nicholas Dagalakis
The objective of this project was to calibrate a commercially available force feedback joystick that could be used for the control of a laser beam optical tweezers test-bed. A calibration box was built to hold the joystick and the load-cell. The joystick

Delocalized Correlations in Twin Light Beams with Orbital Angular Momentum

August 29, 2008
Author(s)
Alberto M. Marino, Vincent Boyer, Raphael C. Pooser, Paul D. Lett, Kristin Lemons, Kevin Jones
We generate intensity-difference-squeezed Laguerre-Gauss twin beams carrying orbital angular momentum using 4-wave mixing (4WM) in a hot atomic vapor. The conservation of orbital angular momentum in the 4WM process is studied as well as the spatial

On the shortest linear straight-line program for computing linear forms

August 29, 2008
Author(s)
Joan Boyar, Philip Matthews, Rene Peralta
We study the complexity of the Shortest Linear Program (SLP) problem, which is to the number of linear operations necessary to compute a set of linear forms. SLP is shown to be NP-hard. Furthermore, a special case of the corresponding decision problem is

Trapped-Ion Quantum Logic Gates Based on Oscillating Magnetic Fields

August 29, 2008
Author(s)
Christian Ospelkaus, Christopher Langer, Jason Amini, Kenton R. Brown, Dietrich G. Leibfried, David J. Wineland
Oscillating magnetic fields and field gradients can be used to implement single-qubit rotations and entangling multi-qubit quantum gates for trapped-ion quantum information processing (QIP). With fields generated by currents in microfabricated surface

VAST 2008 Challenge: Introducing Mini-Challenges

August 29, 2008
Author(s)
Georges Grinstein, Catherine Plaisant, Sharon J. Laskowski, Theresa O'Connell, Jean Scholtz, Mark Whiting
Visual analytics experts realize that one effective way to push the field forward and to develop metrics for measuring the performance of various visual analytics components is to hold an annual competition. In its third year, we restructured the contest

Classification of Microheterogeneity in Solid Samples using mXRF

August 28, 2008
Author(s)
John L. Molloy, John R. Sieber
Micro X-ray Fluorescence (µXRF) has been used to nondestructively investigate elemental heterogeneity by constructing two-dimensional maps of elemental concentrations in reference materials. µXRF allows probing of sample sizes in the microgram and nanogram

The Integration of Molecular Electronic Devices with Traditional CMOS Technologies

August 28, 2008
Author(s)
Nadine E. Gergel-Hackett, Askia A. Hill, Christina A. Hacker, Curt A. Richter
This work describes the development of hybrid circuits composed of silicon-based molecular electronic devices and traditional CMOS technology. In the development of these circuits, we first fabricated individual CMOS-compatible molecular electronic devices

Band offsets of atomic-layer-deposited Al2O3 on GaAs and the effects of surface treatment.

August 27, 2008
Author(s)
Nhan V. Nguyen, Oleg A. Kirillov, Weirong Jiang, Wenyong Wang, John S. Suehle, P. D. Ye, Y. Xuan, N. Goel, Kwang-Woo Choi, Wilman Tsai
In this letter we report the band offsets of the Al/Al2O3/GaAs structure determined by internal photoemission and spectroscopic ellipsometry. The energy barrier height at the Al2O3 and sulfur-passivated GaAs interface is found to be 3.0 eV, which is

Forensic Filtering of Cell Phone Protocols

August 27, 2008
Author(s)
Aurelien M. Delaitre, Wayne Jansen
Phone managers are non-forensic software tools designed to carry out a range of tasks for the user, such as reading and updating the contents of a phone, using one or more of the communications protocols supported by the phone. Phone managers are sometimes

Signature of magnetic phase separation in the ground state of Pr 1 - x Ca x MnO 3

August 27, 2008
Author(s)
Hao Sha, F Ye, Pengcheng Dai, J. A. Fernandez-Baca, D Mesa, Jeffrey Lynn, Y Tomioka, Y Tokura, Jiandi Zhang
Neutron scattering has been used to investigate the evolution of long- and short-range charge-ordered (CO), ferromagnetic, and antiferromagnetic (AF) correlations in single crystals of Pr1−xCaxMnO3. The existence and population of spin clusters as

Diagnosis of Pulsed Squeezing in Multiple Temporal Modes

August 26, 2008
Author(s)
Scott C. Glancy, Emanuel H. Knill, Thomas Gerrits, Tracy S. Clement, Martin J. Stevens, Sae Woo Nam, Richard P. Mirin
When one makes squeezed light by downconversion of a pulsed pump laser, many temporal / spectral modes are simultaneously squeezed by different amounts. There is no guarantee that any of these modes matches the pump or the local oscillator used to measure

Fast, bias-free algorithm for tracking single particles with variable size and shape

August 26, 2008
Author(s)
Andrew J. Berglund, Matthew D. McMahon, Jabez J. McClelland, James A. Liddle
We introduce a fast and robust technique for single-particle tracking with nanometer accuracy.We extract the center-of-mass of the image of a single particle with a simple, iterative algorithm that efficiently suppresses background-induced bias in a

Molecule induced interface states dominate charge transport in Si-alkyl-metal junctions

August 26, 2008
Author(s)
Lam H. Yu, Nadine E. Gergel-Hackett, Christopher D. Zangmeister, Christina A. Hacker, Curt A. Richter, James G. Kushmerick
Abstract. Semiconductor-molecule-metal junctions consisting of alkanethiol mono- layers self-assembled on both p+ and n¡ type highly doped Si(111)wires contacted with a 10 ¹m Au wire in a crossed-wire geometry are examined. Low temperature transport

Neutron-scattering study of the oxypnictide superconductor LaFeAsO 0.87 F 0.13

August 26, 2008
Author(s)
Yiming Qiu, M. Kofu, Wei Bao, S.-H. Lee, Qingzhen Huang, Taner N. Yildirim, John R. Copley, Jeffrey Lynn, T. Wu, G. Wu, X. H. Chen
The recently discovered superconductor LaO0.87F0.13FeAs (TC≈26 K) was investigated using the neutron-scattering technique. No spin-density-wave (SDW) order was observed in the normal state or in the superconducting state, both with and without an applied

NIST Microform Calibration System for Rockwell Hardness Standardization

August 25, 2008
Author(s)
Jun-Feng Song, Samuel R. Low III, Xiaoyu A. Zheng
In the uncertainty budget of Rockwell hardness tests, microform geometric errors of the diamond indenter are a major contributor. The microform calibration of Rockwell diamond indenters has been one of the key steps for Rockwell hardness standardization

Ratio of the Al + and Hg + Optical Clock Frequencies to 17 Decimal Places

August 25, 2008
Author(s)
Wayne M. Itano, Till P. Rosenband, David Hume, P.O. Schmidt, Chin-Wen Chou, A. Brusch, Luca Lorini, Windell Oskay, Robert E. Drullinger, Sarah Bickman, Tara M. Fortier, Jason Stalnaker, Scott A. Diddams, William C. Swann, Nathan R. Newbury, David J. Wineland, James C. Bergquist
Frequency standards (atomic clocks) based on narrow optical transitions in 27Al + and 199Hg + have been developed over the past several years at NIST. These two types of standards are both based on single ions confined in Paul traps, but differ in the

Style Guide for Voting System Documentation

August 25, 2008
Author(s)
Dana E. Chisnell, Susan C. Becker, Sharon J. Laskowski, Svetlana Z. Lowry
The goal of this style guide is to provide specific guidance to improve the usability of documentation used by poll workers and election support staff. The Voting System Documentation Style Guide incorporates best practices for writing documentation as it
Displaying 29701 - 29725 of 74129