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Jungseok Chae, Sangmin An, Georg Ramer, Vitalie Stavila, Glenn Holland, Yohan Yoon, Alec Talin, Mark Allendorf, Vladimir Aksyuk, Andrea Centrone
The atomic force microscope (AFM) offers a rich observation window on the nanoscale, yet many dynamic phenomena are too fast and too weak for direct detection, urging measurement innovation. Integrated cavity-optomechanics is revolutionizing
Srinivasa Ramisetti, Jorge O. Ona Ruales, Stephen Wise, Shantu Amin, Arun Sharma
An efficient synthesis of dibenzo[a,l]tetracene (1) and dibenzo[a,j]tetracene (2) has been developed using Diels-Alder reaction of in situ generated ortho-quinodimethane with phenanthrene-1,4-dione, followed by reductive aromatization as key steps. This
Adam J. Fleisher, David A. Long, Qingnan Liu, Lyn Gameson, Joseph T. Hodges
High-precision measurements of radiocarbon (14C) near or below a fraction modern 14C of one (F14C ≤ 1) are costly, requiring the shipment of samples to accelerator mass spectrometer (AMS) facilities that specialize in reporting rare isotope relative
Sean M. Oliver, Ryan Beams, Sergiy Krylyuk, Arunima Singh, Irina Kalish, Alina Bruma, Francesca Tavazza, Iris Stone, Stephan J. Stranick, Albert Davydov, Patrick M. Vora
The structural polymorphism in transition metal dichalcogenides (TMDs) provides exciting opportunities for developing advanced electronics. For example, MoTe2 crystallizes in the 2H semiconducting phase at ambient temperature and pressure, but transitions
Ian R. Coddington, William C. Swann, Nathan R. Newbury, Paul J. Schroeder, Matthew J. Cich, Jinyu Yang, Brian J. Drouin, Gregory B. Rieker
Spectroscopic studies of planetary atmospheres and high-temperature processes (e.g. combustion) require absorption lineshape models that are accurate over extended temperature ranges. To date, advanced lineshapes, like the speed-dependent Voigt and Rautian
Amber McCreary, Jeffrey R. Simpson, Yuanxi Wang, Daniel Rhodes, Kazunori Fujisawa, Luis Balicas, Madan Dubey, Vincent H. Crespi, M. Terrones, Angela R. Hight Walker
Rhenium disulfide is an exciting material due to its strong in-plane anisotropy, thus offering an additional physical parameter that can be tuned for advanced applications. ReS2 provides a major advantage for optoelectronics as it is both stable in air and
Christina A. Hacker, Robert C. Bruce, Sujitra J. Pookpanratana
Innovation in the electronics industry is tied to interface engineering as devices increasingly incorporate new materials and shrink. Molecular layers offer a versatile means of tuning interfacial electronic, chemical, physical, and magnetic properties
John Mates, Dan Becker, Douglas Bennett, Johnathon Gard, James P. Hays-Wehle, Joseph Fowler, Gene C. Hilton, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Leila R. Vale, Joel Ullom
The number of elements in most cryogenic sensor arrays is limited by the technology available to multiplex signals from the array into a smaller number of wires and readout amplifiers. The largest demonstrated arrays of transition-edge sensor (TES)
Yaxin Zhai, S. Baniya, C. Zhang, Junwen Li, Paul M. Haney, C.-X. Sheng, Z. Vardeny
Two-dimensional (2D) layered hybrid organic-inorganic halide perovskite semiconductors form natural ‘multiple quantum wells' that possess strong spin-orbit coupling due to the heavy elements in their building blocks. This may lead to ‘Rashba-splitting'
Kevin C. Cossel, Eleanor M. Waxman, Fabrizio R. Giorgetta, Michael A. Cermak, Dan Hesselius, Shalom Ruben, William C. Swann, Gregory B. Rieker, Nathan R. Newbury
We demonstrate a new technique for spatial mapping of multiple atmospheric gas species. This system is based on high-precision dual-comb spectroscopy to a retroreflector mounted on a flying multicopter. We measure the atmospheric absorption over long open
Multi-dimensional coherent spectroscopy (MDCS) has become an extremely versatile and sensitive technique for elucidating the structure, composition, and dynamics of condensed matter, atomic, and molecular systems. The appeal of MDCS lies in its ability to
Muhammad I. Afzal, Sofia C. Corzo Garcia, Ulf Griesmann
We describe the prototype of a focal plane imager for the characterization of fabrication errors in diffractive optics. We also demonstrate the use of a high dynamic range imaging method to identify small errors in a hologram and a grating that are
Carrier conductivity and mobility for various semiconductor wafers and crystals were measured by ultrafast above bandgap, optically excited Time-Resolved Terahertz Spectroscopy (TRTS) and Hall Van der Pauw contact methods to directly compare these
Vladimir L. Orkin, Larissa E. Martynova, Michael J. Kurylo III
Abstract Rate constants for the reactions of hydroxyl radicals (OH) with methyl 2,2,2-trifluoroethyl-1-trifluoromethyl ether (CH3-O-CH-(CF3)2 and 4-bromo-3-chloro-3,4,4-trifluoro-1-butene (CH2=CH-CFCl-CF2Br) have been measured over the temperature range
Charles A. Little, Nathan D. Orloff, Christian J. Long, James C. Booth
Complex impedance measurements of fluids provide unique electrical information with important applications for chemical and pharmacological synthesis, and medical diagnostics. Many relevant fluids are ionic. During electrical measurement, ions in the fluid
Bradley Alpert, W.Bertrand (Randy) Doriese, Gene C. Hilton, Lawrence T. Hudson, Young I. Joe, Kelsey Morgan, Carl D. Reintsema, Dan Schmidt, Daniel Swetz, Csilla Szabo-Foster, Joel Ullom, Joseph Fowler, Galen O'Neil, Douglas Bennett
We introduce a new technique for determining x-ray fluorescence line energies and widths, and we present measurements made with this technique of 22 x-ray L lines from lanthanide-series elements. The technique uses arrays of transition-edge sensors
This study considers a physics-based and a kernel-based approach for characterizing pixels in a scene that may be linear (areal mixed) or nonlinear (intimately mixed). The physics-based method is based on earlier studies that indicate nonlinear mixtures in
This article reviews the mechanism of tip enhanced Raman spectroscopy (TERS) and its importance for characterizing graphene. The theoretical foundation of TERS and experimental implementation are discussed. Conventionally, Raman scattering is treated as a
Vladislav P. Gerginov, Sean P. Krzyzewski, Svenja A. Knappe
A scalar magnetic field sensor based on 87Rb vapor millimeter-size cell is described. The magnetometer uses co-propagating pump/probe laser beam, amplitude modulation of the pump beam and non-demolition polarization rotation detection of the probe beam
Li-Hong Xu, E. M. Reid, B. Guislain, Jon T. Hougen, Eugene A. Alekseev, I. Krapivin
Quantum chemistry packages can be used to predict with reasonable accuracy spin-rotation hyperfine interaction constants for methanol, which contains one methyl-top internal rotor. In this work we used these same packages to calculate components of the
Fabio Casu, Aaron Watson, Justin Yost, John Leffler, Gibson Gaylord, Frederic Barrows, Paul A. Sandifer, Dan Bearden, Michael R. Denson
In this study we investigated the metabolic effects of four different commercial soy-based protein products on red drum (Sciaenops ocellatus) using NMR-based metabolomics along with unsupervised principal component analysis (PCA) to evaluate metabolic
The specific refractive index increment (dn/dc) is an essential datum for the accurate quantitation of molar mass averages and distributions (inter alia) of macromolecules when refractometry, static light scattering, and/or viscometry detection are coupled
Donglin Zhao, Qinghe Wu, Luping Yu, Harald Ade, Dean DeLongchamp, Lee J. Richter, Subhrangsu Mukherjee, Andrew Herzing
Morphology can play a critical role in determining function in organic photovoltaic (OPV) systems. Recently molecular acceptors have showed promise to replace¬ fullerene derivatives as acceptor materials in bulk heterojunction solar cells and have achieved
In this paper we examine the two-dimensional tunneling formalism used previously to fit the hydrogen-transfer and internal-rotation splittings in the microwave spectrum of 2 methylmalonaldehyde in an effort to determine the origin of various
We have tested the suitability of a commercial flatbed scanner for digitizing photographic plates used for spectroscopy. The scanner has a bed size of 420 mm by 310 mm and a pixel size of about 10 um. Our tests show that the closest line pairs that can be