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Search Publications

NIST Authors in Bold

Displaying 17051 - 17075 of 73963

A significant-loophole-free test of Bell's theorem with entangled photons

December 16, 2015
Author(s)
Marissa Giustina, Marijn Versteegh, Soren Wengerowsky, Johannes Handsteiner, Armin Hochrainer, Kevin Phelan, Fabian Steinlechner, Johannes Koffler, Larsson Jan-Ake, Carlos Abellan, Waldimar Amaya, Valerio Pruneri, Morgan Mitchell, Joern Beyer, Thomas Gerrits, Adriana Lita, Krister Shalm, Sae Woo Nam, Thomas Scheidl, Rupert Ursin, Bernhard Wittmann, Anton Zeilinger
Local realism is the worldview in which physical properties of objects exist independently of measurement and where physical influences cannot travel faster than the speed of light. Bell's theorem states that this worldview is incompatible with the

A strong loophole-free test of local realism

December 16, 2015
Author(s)
Lynden K. Shalm, Evan Meyer-Scott, B. G. Christensen, Peter L. Bierhorst, Michael A. Wayne, Deny Hamel, Martin J. Stevens, Thomas Gerrits, Scott C. Glancy, Michael S. Allman, Kevin J. Coakley, Shellee D. Dyer, Adriana E. Lita, Varun B. Verma, Joshua C. Bienfang, Alan L. Migdall, Yanbao Zhang, William Farr, Francesco Marsili, Matthew D. Shaw, Jeffrey Stern, Carlos Abellan, Waldimar Amaya, Valerio Pruneri, Thomas Jennewein, Morgan Mitchell, P. G. Kwiat, Richard P. Mirin, Emanuel H. Knill, Sae Woo Nam
We present a loophole-free violation of local realism using entangled photon pairs. We ensure that all relevant events in our Bell test are spacelike separated by placing the parties far enough apart and by using fast random number generators and high

Local photocarrier dynamics in CdTe solar cells under optical and electron beam excitations

December 16, 2015
Author(s)
Heayoung Yoon, Paul M. Haney, Yohan Yoon, Sang M. An, James I. Basham, Nikolai Zhitenev
We investigate local carrier dynamics in n-CdS / p-CdTe solar cells, where the electron-hole pairs are generated by either near-field optical illumination or highly focused electron beam excitation. A focused ion milling process was used to prepare a

Thermodynamic Properties of Polycyclic Aromatic Hydrocarbons

December 16, 2015
Author(s)
Thomas C. Allison, Donald R. Burgess Jr.
Polycyclic aromatic hydrocarbons (PAHs) are molecules that exist on earth due to natural and man-made causes. They are a significant health concern as many PAH compounds are known to be carcinogenic. PAHs are generally thermodynamically stable and

Hopper Scales - Selecting the Appropriate Device

December 15, 2015
Author(s)
John W. Barton
The NIST Office of Weights and Measures (OWM) over time have received a number of inquiries regarding the suitability, use, and testing of hopper-type scales. The nature of those inquiries provides some indication that there is a lack of detailed

Metrological challenges for measurements of key climatological observables, Part 4: Atmospheric relative humidity

December 15, 2015
Author(s)
Allan H. Harvey, J W. Lovell-Smith, Rainer Feistel, Olaf Hellmuth, Stephanie A. Bell, M Heinonen, J R. Cooper
Water in its three ambient phases plays the central thermodynamic role in the terrestrial climate system. Clouds control Earth’s radiation balance, atmospheric water vapour is the strongest “greenhouse” gas, and non-equilibrium relative humidity at the air

Metrological challenges for measurements of key climatological observables: Oceanic salinity and pH, and atmospheric humidity. Part 1: overview

December 15, 2015
Author(s)
Rainer Feistel, Robert Wielgosz, Stephanie A. Bell, M F. Camoes, J R. Cooper, P Dexter, A G. Dickson, P Fisicaro, Allan H. Harvey, M Heinonen, Olaf Hellmuth, H J. Kretzschmar, J W. Lovell-Smith, Trevor J. McDougall, R Pawlowicz, S Seitz, Petra Spitzer, D Stoica, H Wolf, P Ridout
Water in its three ambient phases plays the dominant thermodynamic role for the functioning principles of the terrestrial climate system. Together with clouds, water vapour in the atmosphere is the strongest greenhouse gas (followed by clouds and carbon

Monolithic device for modelocking and stabilization of a frequency comb

December 15, 2015
Author(s)
Kevin L. Silverman, Richard P. Mirin, Ari D. Feldman, Todd E. Harvey, Thomas Schibli, Chien-Chung Lee, Yosuke Hayashi
We demonstrate a device that integrates a III-V semiconductor saturable absorber mirror with a graphene electro-optic modulator, which provides a monolithic solution to modelocking and noise suppression in a frequency comb. The device offers a pure loss

Potential Stable Low-Permeation Rate Standard Based on Micro-machined Silicon

December 15, 2015
Author(s)
Grady S. White, Adrian Verwolf, Chris M. Poling, Nicholas Barbosa, Nikki S. Rentz
Silicon wafers with micro-machined holes were evaluated for use as low permeation standard artifacts. Accuracy, stability, and reliability were assessed. Two experimental techniques were used: chilled mirror hygrometer and mass loss. The wafers exhibited a

Stopping Malware and Unauthorized Software through Application Whitelisting

December 15, 2015
Author(s)
Adam Sedgewick, Murugiah Souppaya, Karen Scarfone, Larry Feldman
This bulletin summarizes the information presented in NIST Special Publication 800-167, "Guide to Application Whitelisting," written by Adam Sedgewick, Murugiah Souppaya and Karen Scarfone. The publication is intended to assist organizations in

Towards a Systematic Threat Modeling Approach for Cyber-physical Systems

December 15, 2015
Author(s)
Goncalo Martins, Sajal Bhatia, Xenofon Koutsoukos, Keith A. Stouffer, CheeYee Tang, Rick Candell
Cyber-Physical Systems (CPS) are systems with seamless integration of physical, computational and networking components. These systems can potentially have an impact on the physical components, hence it is critical to safeguard them against a wide range of

Annual Manufacturing Review

December 14, 2015
Author(s)
Douglas Thomas, Anand M. Kandaswamy
This report provides an overview of the US manufacturing industry. There are three aspects of U.S. manufacturing that are considered: (1) how the US industry compares to other countries, (2) the trends in the domestic industry, and (3) the industry trends

Beam-Scanning for Rapid Coherent Raman Hyperspectral Imaging

December 14, 2015
Author(s)
Seungwan Ryu, Charles Camp, Ying Jin, Marcus T. Cicerone, Young Jong Lee
Coherent Raman imaging requires high peak power laser pulses to maximize the nonlinear multiphoton signal generation, but accompanying photo-induced sample damage often poses a challenge to microscopic imaging studies. We demonstrate that a beam-scanning

Comparative study of methods to measure the density of Cementitious powders

December 14, 2015
Author(s)
Michelle A. Helsel, Chiara F. Ferraris, Dale P. Bentz
The accurate measurement of the density of hydraulic cement plays an essential role in the determination of concrete mixture proportions. As more supplementary cementitious materials (SCM), such as fly ash and slag, or cement replacement materials, such as

High-performing visible-blind photodetectors based on SnO2/CuO nanoheterojunctions

December 14, 2015
Author(s)
Ratan K. Debnath, Ting Xie, MD R. Hasan, Nhan V. Nguyen, Abhishek Motayed
We report on the significant performance enhancement of SnO2 thin film ultraviolet (UV) photodetectors (PDs) through incorporation of CuO/SnO2 pn nanoscale heterojuctions. The nanoheterojunctions are self-assembled by sputtering Cu clusters that oxidize in

Inventory and Flow Time in the US Manufacturing Industry

December 14, 2015
Author(s)
Douglas Thomas, Anand M. Kandaswamy
Advancements in the efficient use of inputs, such as land and labor, have been a key driver of per capita income growth throughout history. One method for identifying potential efficiency improvements is lean manufacturing or lean production, a set of

Rotational Dynamics of Organic Cations in the CH 3 NH 3 Pbl 3 Perovskite

December 14, 2015
Author(s)
Tianran Chen, Benjamin J. Foley, Bahar NMN Ipek, Madhu Sudan Tyagi, John R. Copley, Craig Brown, Joshua J. Choi, Seunghun Lee Lee
All semiconductors can generate free charges by absorbing light. However, not all semiconductors are high performance photovoltaic materials, because the charge carriers with opposite signs, electrons and holes, quickly annihilate each other. High
Displaying 17051 - 17075 of 73963
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