U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications

NIST Authors in Bold

Displaying 10951 - 10975 of 74855

Elementary Again

April 6, 2018
Author(s)
Mark W. Keller
Mark Keller explains how the elementary charge will soon be reinstated in metrology - and why it got sidelined in the first place.

Superconducting optoelectronic networks I: general principles

April 6, 2018
Author(s)
Jeffrey M. Shainline, Sonia M. Buckley, Adam N. McCaughan, Jeffrey T. Chiles, Richard P. Mirin, Sae Woo Nam
The design of neural hardware is informed by the prominence of differentiated processing and information integration in cognitive systems. The central role of communication leads to the principal assumption of the hardware platform: signals between neurons

Superconducting optoelectronic networks II: receiver circuits

April 6, 2018
Author(s)
Jeffrey M. Shainline, Sonia M. Buckley, Adam N. McCaughan, Manuel C. Castellanos Beltran, Christine A. Donnelly, Michael L. Schneider, Richard P. Mirin, Sae Woo Nam
Circuits using superconducting single-photon detectors and Josephson junctions to perform signal reception, synaptic weighting, and integration are investigated. The circuits convert photon-detection events into flux quanta, the number of which is

Mid-infrared frequency comb generation via cascaded quadratic nonlinearities in quasi-phase-matched waveguides

April 5, 2018
Author(s)
Abijith S. Kowligy, Alexander J. Lind, Daniel D. Hickstein, David R. Carlson, Henry R. Timmers, Nima Nader, Flavio Caldas da Cruz, Gabriel G. Ycas
We demonstrate mid-infrared (MIR) frequency comb generation in periodically poled lithium niobate (PPLN) waveguides pumped by nanojoule pulses from a 1.5 um mode-locked Er:fiber laser. The cascaded-c(2) nonlinearity in PPLN yields a nearly octave-spanning

A new magnet design for future Kibble balances

April 4, 2018
Author(s)
Stephan Schlamminger, Shisong Li, Michael Stock
We propose a new permanent magnet system for Kibble balance experiments, which combines advantages of the magnet designs invented by the National Physical Laboratory (NPL) and by the Bureau International des Poids et Mesures (BIPM). The goal of the

Femtosecond timekeeping: slip-free optical clockwork for optical timescales

April 3, 2018
Author(s)
Daniel I. Herman, Stefan Droste, Esther Baumann, Jonathan Roslund, Dmitriy Churin, Arman Cingoz, Jean-Daniel Deschenes, Isaac H. Khader, William C. Swann, Craig W. Nelson, Nathan R. Newbury, Ian R. Coddington
The generation of true optical time standards will require the conversion of the highly stable optical frequency output of an optical atomic clock to a high-fidelity time output. We demonstrate comb-based clockwork that phase-coherently integrates ~7x10e20

High temperature performance of the HITEMP2010 and HITRAN Online databases: comparison with frequency comb measurements of water vapor absorption from 6800 cm-1 to 7200 cm-1

April 3, 2018
Author(s)
Paul J. Schroeder, D Pfotenhauer, J Yang, William C. Swann, Ian R. Coddington, Nathan R. Newbury, Greg B. Rieker
The HITEMP2010 and HITRAN Online databases are important tools for predicting molecular absorption under various environmental conditions. At room temperature the databases can be quite accurate, owing to their development using room temperature absorption

Influence of Ion Solvation on the Properties of Electrolyte Solutions

April 3, 2018
Author(s)
Marat Andreev, Juan J. DePablo, Alexandros Chremos, Jack F. Douglas
It is widely appreciated that the addition of salts to water leads to significant changes in the thermodynamic and dynamic properties of these aqueous solutions, which have great significance in biology and manufacturing applications. However, no

The Multiplicative Complexity of 6-variable Boolean Functions

April 3, 2018
Author(s)
Cagdas Calik, Meltem Sonmez Turan, Rene C. Peralta
The multiplicative complexity of a Boolean function is the minimum number of AND gates that are necessary and sufficient to implement the function over the basis (AND, XOR, NOT). Finding the multiplicative complexity of a given function is computationally

UNCERTAINTY IN MULTI-SCALE CREEP RUPTURE LIFE MODELING AND A NEW APPROACH TO ESTIMATING FREQUENCY OF IN-SERVICE INSPECTION OF COMPONENTS AT ELEVATED TEMPERATURES (*)

April 3, 2018
Author(s)
Jeffrey T. Fong, Nathanael A. Heckert, James J. Filliben, Marvin J. Cohn
Uncertainty in modeling the creep rupture life of a full-scale component using experimental data at microscopic (Level 1), specimen (Level 2), and full-size (Level 3) scales, is addressed by applying statistical theory of prediction intervals, and that of

6 LiF:ZnS(Ag) Mixture Optimization for a Miniature Highly Efficient Cold Neutron Detector

April 2, 2018
Author(s)
A. Osovizky, Kevin N. Pritchard, Jeffrey B. Ziegler, Louis E. Binkley, Y. Yehuda-Zada, Peter NMN Tsai, Alan Keith Thompson, P. Yvonne Barnes, Kerry Siebein, Nancy Hadad, M. Jackson, C. Hurlbut, R. Ibberson, George M. Baltic, Charles Majkrzak, Nicholas C. Maliszewskyj
We report the optimization of a ^6^LiF:ZnS(Ag) scintillator mixture for an ultrathin (2nm), highly efficient cold neutron dector. Preliminary results with early protypes demonstrate excellent for 3.62 meV (4.75 Angstrom wavelenght) neutrons but mediocre

Method for Determining the Electrical Shape of a Scanning Probe Microscope Tip

April 2, 2018
Author(s)
Joseph J. Kopanski, Malcolm Regan, Lin You
Knowledge of the actual electrical tip shape can be used to better understand electric field gradients measured with eSPMs and to determine the suitability of various types of conducting SPM tips for electrical measurements. For co-axially shielded tips

Addressing Quality Assurance Issues in 3D Firearm and Toolmark Imaging

April 1, 2018
Author(s)
Michael T. Stocker, Robert M. Thompson, Johannes A. Soons, Thomas B. Renegar, Xiaoyu A. Zheng
The emerging capability for measuring and analyzing the three-dimensional (3D) surface topography of forensic samples is expected to have a profound impact on firearm and toolmark identification. As forensic laboratories are working to integrate 3D
Displaying 10951 - 10975 of 74855