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This study describes the use of inkjet printing for the preparation of test materials containing gold nanoparticles (AuNPs) on a biologically relevant matrix, and discusses the methods of using time-of-flight secondary ion mass spectrometry (ToF-SIMS) for
This is the first in a series of articles which present a new framework for computing the uncertainty in electron excited X-ray microanalysis measurements. This article will discuss the framework and apply it to a handful of simple but useful sub
Dmitry Kurouski, Alexandre Dazzi, Renato Zenobi, Andrea Centrone
The advent of nanotechnology, and the need to understand the chemical composition at the nanoscale, has stimulated the convergence of IR and Raman spectroscopy with scanning probe methods, resulting in new nanospectroscopy paradigms. Here we review two of
Georg Ramer, Mohit Tuteja, Joseph R. Matson, Marcelo I. Davanco, Thomas G. Folland, Andrey Kretinin, Takashi Taniguchi, Kenji Watanabe, Kostya Novoselov, Joshua D. Caldwell, Andrea Centrone
The anisotropy of hexagonal boron nitride (hBN) crystals gives rise to hyperbolic phonon polaritons (HPhPs), notable for their volumetric frequency-dependent angular propagation and strong confinement. For frustum (truncated nanocone) structures, theory
Dipti Goyal, Sean W. Buechele, Amy C. Gall, Samuel C. Sanders, Csilla I. Szabo-Foster, Roshani Silwal, Endre A. Takacs, Yuri Ralchenko
High-resolution x-ray spectra were recorded at the National Institute of Standards and Technology (NIST) electron beam ion trap (EBIT) using two Johann-type crystal spectrometers, with their dispersion planes oriented parallel and perpendicular to the beam
Radislav A. Potyrailo, J. Brewer, B. Cheng, M. A. Carpenter, N. Houlihan, Andrei Kolmakov
Existing sensors for gaseous species often degrade their performance because of the loss of the measurement accuracy in the presence of interferences. Thus, new sensing approaches are required with improved sensor selectivity. We are developing a new
L. M. Martinez, H. Iturriaga, R. Olmos, L. Shao, Y. Liu, Thuc Mai, C. Petrovic, Angela R. Hight Walker, S. R. Singamaneni
van der Waals (vdW) engineering of magnetism is a topic of increasing research interest in the community at present. We study the magnetic properties of quasi-two-dimensional layered vdW Mn3Si2Te6 (MST) crystals upon proton irradiation as a function of
Christopher M. Arble, Hongxuan Gou, Evgheni Strelcov, Brian D. Hoskins, Patrick Zeller, Matteo Amati, Luca Gregoratti, Andrei A. Kolmakov
Ambient pressure X-ray photoelectron spectroscopy (APXPS) has become an effective tool to interrogate chemical states at surfaces relevant to real operational conditions. Herein we employ a graphene-capped microvolume array sample platform for scanning
Ann C. Chiaramonti Debay, Luis Miaja Avila, Benjamin W. Caplins, Paul T. Blanchard, Norman A. Sanford, Brian Gorman, David R. Diercks
This paper reports construction of an extreme ultraviolet (EUV) radiation-triggered atom probe tomograph and describes the results from initial experiments on amorphous SiO2. Femtosecond-pulsed coherent EUV radiation of 29.6 nm wavelength (41.85 eV photon
The rheology of crystallizing polymers is critical to polymer processing, but our current understanding of how crystallinity affects rheology during crystallization is lacking. The challenge is twofold: first, we must measure rheology simultaneously with
Timothy J. Magnanelli, Sebastian Engmann, Jared K. Wahlstrand, John C. Stephenson, Lee J. Richter, Edwin J. Heilweil
We interrogate polarization anisotropy associated with charge conduction in films of the block co polymer PCDTPT, consisting of alternating cyclopenta dithiophene (donor) and thiadiazolo pyridine (acceptor) units with respect to sample morphology. Film
Dipti Goyal, A. Borovik, Jr., R. Silwal, Joan M. Dreiling, Amy C. Gall, Endre Takacs, Yuri Ralchenko
We present accurate spectroscopic measurements and detailed theoretical analysis of inner-shell LM$n$ and LN$n$ ($n$ $\geq$ 4) dielectronic resonances (DR) in highly-charged M-shell ions of tungsten. The x-ray emission from W$^49+}$ through W$^64+}$ was
Antonio L. Levy, Andrei Sushkov, Fengguang Liu, Bing Shen, Ni Ni, Howard D. Drew, Gregory Jenkins
Chiral pumping from optical electric fields oscillating at THz frequencies is observed in the Weyl material TaAs with electric and magnetic fields aligned along both the a- and c-axes. Free carrier spectral weight enhancement is measured directly for the
Multidimensional coherent spectroscopy measures the third-order polarization response of a system to reveal microscopic electronic and many-body phenomena. Applied to semiconductor nanostructures, it can distinguish homogeneous and inhomogeneous broadening
Low density charge mobility from below bandgap, two-photon photoexcitation of bulk Silicon (Si) is interrogated using time-resolved terahertz spectroscopy (TRTS). Total charge mobility is measured as a function of excitation frequency and fluence (charge
Amber D. McCreary, Jeffrey R. Simpson, Thuc T. Mai, Robert D. McMichael, Jason E. Douglas, Nicholas P. Butch, Cindi L. Dennis, Rolando Valdes Aguilar, Angela R. Hight Walker
Recently it was discovered that van der Waals-bonded magnets retain long range magnetic ordering even down to a monolayer thickness, opening many avenues in fundamental physics and potential applications of these fascinating materials. One example is FePS3
Hans Pieter Mumm, Denis E. Bergeron, Mark Tyra, Jerome LaRosa, Svetlana Nour, T.J. Langford, Dimitry A. Pushin
Neutral particle detection in high-background environments is greatly aided by the ability to easily load 6Li into liquid scintillators. We describe a readily available and inexpensive liquid scintillation cocktail stably loaded with up to 1 % Li by mass
Malcolm S. Durkin, Galen C. O'Neil, William B. Doriese, Johnathon D. Gard, Gene C. Hilton, Jozsef Imrek, Nathan J. Ortiz, Carl D. Reintsema, Robert W. Stevens, Daniel S. Swetz, Joel N. Ullom
Time division multiplexing (TDM) uses a digital flux-locked loop (DFLL) to linearize each first-stage SQUID amplifier. Presently, the dynamic range of our TDM systems is limited by the use of a proportional-integral controller to maintain the DFLL. In this
Gaoxiang Liu, Manuel Diaz-Tinoco, Sandra M. Ciborowski, Chalynette Martinez-Martinez, Svetlana Lyspustina, Jay H. Hendricks, Vincent Ortiz, Kit H. Bowen
The hydrogen sulfide trimer and tetramer anions, (H2S)3– and (H2S)4–, were generated by Rydberg electron transfer and studied via a synergy between velocity-map imaging anion photoelectron spectroscopy and high-level quantum chemical calculations. The
Xiaojie Liu, Ashish Chanana, Uyen Huynh, Fei Xue, Paul M. Haney, Steve Blair, Xiaomei Jiang, Valy Vardeny
The two-dimensional (2D)-phenylethyl ammonium lead iodide (2D-PEPI) is an exemplary hybrid organic-inorganic halide perovskite, possessing large spin-orbit coupling and forming multiple quantum wells (MQW). We have used helicity-dependent steady state
Sean M. Oliver, Joshua Young, Sergiy Krylyuk, Thomas L. Reinecke, Albert Davydov, Patrick M. Vora
Alloyed transition metals dichalcogenides (TMDs) provide the unique opportunity for coupling band engineering and valleytronic phenomena in an atomically-thin platform. However, valley properties remain largely unexplored in TMD alloys. Here, we
Direct digital synthesis in concert with an electro-optic phase modulator was employed to generate optical frequency combs with tooth spacings as low as 100 Hz. These combs were utilized to probe electromagnetically induced transparency (EIT) and hyperfine