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W.R. Clements, Jelmer Renema, Andreas Eckstein, Antonio A. Valido, Adriana Lita, Thomas Gerrits, Sae Woo Nam, Steven Kolthammer, Joonsuk Huh
We study the impact of experimental imperfections on a recently proposed protocol for performing quantum simulations of vibronic spectroscopy. Specifically, we propose a method for quantifying the impact of these imperfections, optimizing an experiment to
Current-to-voltage converters are used in many photometric and radiometric applications. The calibration of current- to-voltage converters at a few input currents is not always sufficient to understand the linearity and the bias of a device. Many devices
Galan Moody, Takeshi Suzuki, Rohan Singh, Marc Assman, Manfred Bayer, Arne Ludwig, Andreas Wieck, Steven T. Cundiff
The dephasing mechanisms of p-shell and s-shell excitons in an InAs self-assembled quantum dot ensemble are examined using two-dimensional coherent spectroscopy (2DCS). 2DCS provides a comprehensive picture of how the energy level structure of dots affects
Slavomir Nemsak, Evgheni Strelcov, Hongxuan Guo, Brian Hoskins, Tomas Duchon, D Muller, Alexander Yulaev, Ivan Vlassiouk, Alexander Tselev, Andrei Kolmakov
Recent developments in environmental and liquid cells equipped with electron transparent graphene windows have enabled traditional surface science spectromicroscopy tools, such as XPS, PEEM, and SEM to be applied to study solid-liquid and liquid-gas
We perform contactless mobility measurements in ZnSe, ZnTe, GaP, CdS, and GaSe in an optical pump, THz probe experiment. By using two-photon excitation, one excites the entire sample thickness to produce measurable signals at 1013 carriers/cm3 or higher
Mary Kombolias, Jan Obrzut, Karl Montgomery, Michael T. Postek, Dianne L. Poster, Yaw S. Obeng
Product composition and quality test methods for the paper and pulp industry remain rooted in manual, ex-situ, wet-bench chemistry techniques and are highly subjective. For example, the standard method for determining the furnish of paper, TAPPI T 401
Adam J. Biacchi, Son T. Le, Brian G. Alberding, Joseph A. Hagmann, Sujitra J. Pookpanratana, Edwin J. Heilweil, Curt A. Richter, Angela R. Hight Walker
Colloidal-based solution syntheses offer a scalable and cost-efficient means of producing 2D nanomaterials in high yield. While much progress has been made towards the controlled and tailorable synthesis of semiconductor nanocrystals in solution, it
We demonstrate optical and electrical property enhancement of solar cells using a variety of dielectric nano-resonator array coatings. First, we study close-packed silicon dioxide (SiO2) nano-resonator arrays on top of silicon (Si) and gallium arsenide
Lily Northcutt, Sara Orski, Kalman D. Migler, Anthony Kotula
Material extrusion additive manufacturing processes force molten polymer through a printer nozzle at high (> 100 s-1) wall shear rates prior to cooling and crystallization. These high shear rates can lead to flow-induced crystallization in common polymer
A non-tomographic approach based on polarization-dependent infrared (IR) spectroscopy is proposed for a simultaneous measurement of the 3D angles and the orientational order parameter of a molecular orientation distribution. Unlike conventional
Refractive index retrievals (also termed inverse Mie methods or optical closure) have seen considerable use as a method to extract the refractive index of aerosol particles from measured optical properties. Retrievals of an aerosol refractive index use two
Silicon wafer-based internal reflection elements (IREs) present many practical advantages over the prisms conventionally used for attenuated total reflection spectroscopy in the infrared. We examine two methods of using minimally prepared IREs that have
Yusuf S. Aytekin, Mustafa Koturk, Adam Zaczek, Timothy M. Korter, Edwin J. Heilweil, Okan Esenturk
One of the most commonly used nonsteroidal anti-inflammatory active pharmaceutical ingredient called Meloxicam has been characterized spectroscopically both by Terahertz (THz) time domain spectroscopy (THz-TDS) and by Fourier Transform Infrared (FTIR)
Edwin J. Heilweil, Rachel L. Meyer, Tara M. Biser, Anet D. Zhandosova, Christopher J. Stromberg
Coupling photosensitizers with [FeFe]-hydrogenase model compounds can potentially create light- driven catalysts for production of hydrogen gas from acidic protons. Though there have been many studies on the synthesis, kinetics, and reaction mechanisms of
Diana Ortiz-Montalvo, Edward P. Vicenzi, Nicholas W. Ritchie, Carol A. Grissom, Richard A. Livingston, Zoe Weldon-Yochim, Joseph M. Conny, Scott A. Wight
Discoloration on the Smithsonian Institution Building and Enid A. Haupt Garden gateposts was recently revealed to be related to a Mn enriched rock varnish. Mn does not appear to be derived locally from the building stone; therefore, its source is likely
Ryan C. Nieuwendaal, Dean M. DeLongchamp, Martin Heeney, Jan Hummelen, Chad R. Snyder, Ronald L. Jones, Sebastian Engmann, Lee J. Richter, Zhuping Fei, Alex Sieval
We introduce a new application of solid state NMR measurements towards characterizing the donor-acceptor interfaces within bulk heterojunction (BHJ) films. Rotational echo double resonance (REDOR) is used to measure dipolar couplings between 13C nuclei on
Johnathon D. Gard, Daniel T. Becker, Douglas A. Bennett, Joseph W. Fowler, Gene C. Hilton, John A. Mates, Carl D. Reintsema, Daniel R. Schmidt, Daniel S. Swetz, Joel N. Ullom
The readout requirements for instruments based on transition-edge sensors (TESs) have dramatically increased over the last decade as demand for systems with larger arrays and faster sensors has grown. Emerging systems are expected to contain many thousands
Seungwan Ryu, Xiaohui Liu, Ying Jin, Jirun Sun, Young Jong Lee
We investigate multiple hydrogen bonding interactions in a binary mixture of cross-linking resin monomers: urethane dimethacrylate (UDMA) and triethylene glycol-divinylbenzyl ether (TEG-DVBE). We analyze infrared (IR) absorption spectra observed at various
Varun Verma, Martin Stevens, Richard Mirin, Sae Woo Nam, Li Chen, Dirk Schwarzer, Jascha A. Lau
We evaluate the performance of a mid-infrared emission spectrometer operating at wavelengths between 2 and 7 υm based on an amorphous tungsten silicide (a-WSi) superconducting nanowire single-photon detector (SNSPD). To demonstrate the spectrometer's
Sujitra J. Pookpanratana, Katelyn Goetz, Emily G. Bittle, Hamna Haneef, Lin You, Christina A. Hacker, Steven W. Robey, Oana Jurchescu, Ruslan Ovsyannikov, Erika Giangrisostomi
The transport properties of electronic devices made from single crystalline molecular semiconductors outperform those composed of thin-films. To further understand the superiority of these extrinsic properties, an understanding of the intrinsic electronic
C.H. L. Patty, David Luo, Frans Snik, Freek Ariese, Wybren J. Buma, Inge L. ten Kate, Rob J. van Spanning, William Sparks, Thomas Germer, Gy?z? Garab, Michael W. Kudenov
Spectropolarimetry of intact plant leaves allows to probe the molecular architecture of vegetation photosynthesis in a non-invasive and non-destructive way and, as such, can offer a wealth of physiological information. In addition to the molecular signals
Yohan Yoon, Dongheon Ha, Ik Jae Park, Paul M. Haney, Sangwook Lee, Nikolai Zhitenev
In this work, we study spatially-resolved generation of photocurrent of methylammonium lead iodide (CH3NH3PbI3) perovskite solar cells to reveal the microscopic effects of annealing temperature and degradation under light exposure. Correlating a novel
In future quantum communication systems, single photons will be required to possess very narrow linewidths and accurate wavelengths for efficient interaction with quantum memories. Spectral characterization of such single photon sources is necessary and