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Search Publications

NIST Authors in Bold

Displaying 5101 - 5125 of 74359

A six-octave optical frequency comb from a scalable few-cycle Erbium fiber laser

March 11, 2021
Author(s)
Daniel Lesko, Henry R. Timmers, Sida Xing, Abijith S. Kowligy, Alexander Lind, Scott Diddams
A coherent, compact and robust light source with coverage from the ultraviolet to the infrared is desirable for heterodyne super-resolution imaging1, broadband infrared microscopy2, protein structure determination3 and standoff trace-gas detection4. To

Classical Spin Liquid or Extended Critical Range in h-YMnO 3 ?

March 11, 2021
Author(s)
Sofie Janas, Jakob Lass, Ana-Elena Tutueanu, Morten L. Haubro, Christof Niedermayer, Uwe Stuhr, Guangyong Xu, Dharmalingam Prabhakaran, Pascale P. Deen, Sonja Holm-Dahlin, Kim Lefmann
Inelastic neutron experiments on the classical triangular-lattice frustrated antiferromagnet h-YMnO 3 reveal diffuse, gapless magnetic excitations present both far below and far above the ordering temperature, TN. The correlation length of the excitations

Contactless Fingerprint Capture and Data Interchange Best Practice Recommendation

March 11, 2021
Author(s)
Shahram Orandi, John M. Libert, Craig I. Watson, Gregory Fiumara, John Grantham
While contactless fingerprint capture devices stand to provide for many benefits, images from this nascent technology are sufficiently different than traditional contact-collected images thereby warranting the separation of these new contactless

Mitigating finite bandwidth effects in time-division- multiplexed SQUID readout of TES arrays

March 11, 2021
Author(s)
Malcolm Durkin, Joseph S. Adams, Simon Bandler, James A. Chervenak, Ed Denison, W.Bertrand (Randy) Doriese, Shannon Duff, Fred M. Finkbeiner, Joseph Fowler, Johnathon Gard, Gene C. Hilton, Ruslan Hummatov, Kent Irwin, Young I. Joe, Richard L. Kelley, Caroline A. Kilbourne, Antoine R. Miniussi, Kelsey Morgan, Galen O'Neil, Christine Pappas, Frederick S. Porter, Carl D. Reintsema, Kazuhiro Sakai, Stephen J. Smith, Robert W. Stevens, Daniel Swetz, Paul Szypryt, Joel Ullom, Leila R. Vale, Nicholas A. Wakeham
Time division multiplexing (TDM) is being developed as the readout technology of the X-ray integral field unit (X-IFU), a 3,168-pixel X-ray transition-edge sensor (TES) imaging spectrometer that is part of the European Space Agency's Athena satellite

Phonon redshift and Hubble friction in an expanding BEC

March 11, 2021
Author(s)
Stephen Eckel, Ted Jacobson
We revisit the theoretical analysis of an expanding ring-shaped Bose-Einstein condensate. Starting from the action and integrating over dimensions orthogonal to the phonon's direction of travel, we derive an effective one-dimensional wave equation for

A new model dielectric function for loss functions and electron damping

March 10, 2021
Author(s)
Eric L. Shirley
Trends in the zeroth frequency moment of the imaginary part of the dielectric function are studied for a wide range of metals, semiconductors and insulators. These results are combined with estimates for the inverse-first moment (related by Kramers-Kronig

Betraying excitonic processes and chemical bonding in MoS2 by x-ray-absorption near-edge structure and resonant-Auger electron emission

March 10, 2021
Author(s)
Joseph Woicik, Nicholas F. Quackenbush, Conan Weiland, Eric L. Shirley, Abdul K. Rumaiz, Michael T. Brumbach, James M. Ablett
Electron core-hole processes at absorption edges sport several signatures, primarily in the form of bound states and/or excitonic enhancement. Through analysis of the resonant-Raman Auger effect for the 2-dimensional transition-metal dichalcogenide MoS2

Charge-transfer satellites in the photoemission and x-ray absorption spectra of SrTiO3 and TiO2: Experiment and first-principles theory

March 10, 2021
Author(s)
Eric L. Shirley, Joseph Woicik, Cherno Jaye, Daniel A. Fischer, Abdul K. Rumaiz, Joshua J. Kas, John J. Rehr, Conan Weiland
Complete ab initio real-time cumulant and Bethe-Salpeter-equation calculations accurately capture the detailed satellite structure observed in both the photoemission and x-ray absorption spectra of the transition-metal compounds SrTiO3 and TiO2. Real-space

Core-hole processes in photoemission and x-ray absorption by resonant-Auger electron spectroscopy and first-principles theory

March 10, 2021
Author(s)
Eric L. Shirley, Joseph Woicik, Conan Weiland, James M. Ablett, Abdul K. Rumaiz, Michael T. Brumbach, Joshua J. Kas, John J. Rehr
The electron-core-hole interaction is critical for proper interpretation of core-level spectroscopies commonly used as structural tools in materials' science. Resonant Auger- electron spectroscopy can uniquely identify exciton, shake, and charge-transfer

The OCEAN Project

March 10, 2021
Author(s)
Eric L. Shirley, John T. Vinson, Keith Gilmore
This chapter presents a high-level description of a suite of programs denoted by the acronym OCEAN (Obtaining Core Excitation spectra ab initio and with NBSE), where NBSE denotes the underlying NIST Bethe-Salpeter Equation program. The main computational

Broadband thermomechanically limited sensing with an optomechanical accelerometer

March 9, 2021
Author(s)
Feng Zhou, Yiliang Bao, Ramgopal Madugani, David Long, Jason J. Gorman, Thomas W. LeBrun
Cavity optomechanics has enabled precision measurements with unprecedented levels of sensitivity, including the detection of attonewton forces, nanoparticles, magnetic fields, and gravitational waves. In most cases, detection is performed in a narrow

Hydration of Hydrophilic Cloth Facial Coverings Greatly Increases the Filtration Properties for Nanometer and Micrometer-sized Particles

March 8, 2021
Author(s)
Christopher D. Zangmeister, James Radney, Matthew E. Staymates, Edward P. Vicenzi, Jamie Weaver
Filtration efficiencies (FE) of natural, synthetic, and blended fabrics were measured as a function of relative humidity (RH) for particles with mobility diameters between 50 nm and 825 nm. Fabrics were equilibrated at 99 % RH, mimicking conditions

Origin of Magnetovolume Effect in a Cobaltite

March 8, 2021
Author(s)
Ping Miao, Zhijian Tan, Sanghyun Lee, Yoshihisa Ishikawa, Shuki Torii, Masao Yonemura, Akihiro Koda, Kazuki Komatsu, Shinichi Machida, Asami Sano-Furukawa, Takanori Hattori, Xiaohuan Lin, Kuo Li, Takashi Mochiku, Ryosuke Kikuchi, Chizuru Kawashima, Hiroki Takahashi, Qingzhen Huang, Shinichi Itoh, Ryosuke Kadono, Yingxia Wang, Feng Pan, Kunihiko Yamauchi, Takashi Kamiyama

Path-integral calculation of the fourth virial coefficient of helium isotopes

March 8, 2021
Author(s)
Giovanni Garberoglio, Allan H. Harvey
We use the path-integral Monte Carlo (PIMC) method and state-of-the-art two-body and three-body potentials to calculate the fourth virial coefficient D(T) of 4He and 3He as a function of temperature from 2.6 K to 2000 K. We derive expressions for the

Synthesis, Structural and Sorption Characterization of a Hofmann Compound, Ni(3-Methy-4,4'-bipyridine)[Ni(CN)4]

March 6, 2021
Author(s)
Winnie Wong-Ng, Jeffrey T. Culp, Daniel Siderius, Yu-Sheng Chen, S. Y. G. Wang, Andrew J. Allen, Eric J. Cockayne
Crystal structure of the guest-free Ni(CN)4-based metal organic framework Ni(3-Methy-4,4'-bipyridine)[Ni(CN)4] (nicknamed Ni-BpyMe(A)), was determined to be orthorhombic, Pmma, a= 12.6025(4) Å, b=7.3324(3) Å, c=11.3095(4) Å, V=1045.07 (2) Å3 and Z=2

Single-cell measurement of plasmid copy number and promoter activity

March 5, 2021
Author(s)
Bin Shao, Jayan Rammohan, Daniel Anderson, Nina Alperovich, David J. Ross, Christopher Voigt
We have developed a method to simultaneously count plasmid DNA, RNA transcripts, and protein expression in single living bacteria. From these data, the activity of a promoter in units of RNAP/s can be inferred. This work facilitates the reporting of

Uncertainty Quantification of Atomistic (DFT and MD), Mesoscale (PFM) and Continuum (CALPHAD) Methods and the Impact on Thermodynamic Models of Metals: A Review

March 5, 2021
Author(s)
Gabriel Joshua, Noah Paulson, Thien Duong, Francesca Tavazza, Chandler Becker, Santanu Chaudhuri, Stan Marious
Design of improved metals relies on multi-scale computer simulations to provide thermodynamic properties when experiments are difficult to conduct. In particular, atomistic methods such as Density Functional Theory (DFT) and Molecular Dynamics (MD) have
Displaying 5101 - 5125 of 74359