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Photodetectors converting light signals into detectable photocurrents are ubiquitously in use today. To improve the compactness and performance of next-generation devices and systems, low dimensional materials provide rich physics to engineering the light
The past decade saw the emergence of new temperature sensors that have the potential to disrupt a century-old measurement infrastructure based on resistance thermometry. In this review we present an overview of emerging technologies that are either in the
Infrared (IR) spectroscopy is a broadly applicable, composition sensitive analytical technique. By leveraging the high spatial resolution of atomic force microscopy (AFM), the photothermal effect, and wavelength-tunable lasers, AFM IR enables IR
In recent years, interesting materials have emerged which are only available as µm-scale flakes, and whose novel physics might be better understood through broadband microwave spectroscopy; examples include twisted bilayer graphene [1], 2D materials in
A new THz difference-frequency chirped-pulse dual-comb method based on electro-optic phase modulators (EOMs) and two near-visible continuous wave lasers is used to perform high resolution spectroscopy and to magnify the rapid passage signal response.
We present a multi-frequency DIAL system based on a fast-switching wavelength source and fiber optic amplification to acquire range-resolved dry-air CO2 concentrations over the city of Boulder, Colorado USA
A ten wavelength DIAL system based on a 100 Hz optical parametric oscillator (OPO) is used to simultaneously acquire range-resolved and integrated path dry-air CO2 concentrations from soft cloud targets in Boulder, Colorado.
Bruce D. Ravel, Tatiana Konstantinova, Phillip Michael Maffettone, Stuart Campbell, Andi Barbour, Daniel Olds
Imaging, scattering, and spectroscopy are fundamental in understanding and discovering new functional materials. Contemporary innovations in automation and experimental techniques have led to these measurements being performed much faster and with higher
The development of new characterization methods has resulted in innovative studies of the properties of two-dimensional (2D) materials. Observations of nanoscale heterogeneity with scanning probe microscopy methods have led to efforts to further understand
We present passive absorption-based ranging using long-wave infrared hyperspectral measurements of an outdoor scene. Regularization and parametric modeling of transmittance enable good accuracy without knowing temperatures or emissivities of scene objects
Swapnil Mhatre, Ngoc Thanh Mai Tran, Heather Hill, Dipanjan Saha, Angela R. Hight Walker, Chi-Te Liang, Randolph Elmquist, David B. Newell, Albert Rigosi
Cherno Jaye, Daniel A. Fischer, Calvin Quilty, Patrick West, Wenzao Li, Mikaela Dunkin, Garrett Wheeler, Steven Ehrlich, Lu Ma, Esther Takeuchi, Kenneth Takeuchi, David Bock, Amy Marschilok
NMC is a commercially successful Li-ion battery cathode due to its high energy density; however, its delivered capacity must be intentionally limited to achieve capacity retention over extended cycling. To design next-generation NMC batteries with longer
Evan Jahrman, Lee L. Yu, William P. Krekelberg, David Sheen, Thomas C. Allison, John L. Molloy
The toxicity and bioavailability of arsenic is heavily dependent on its speciation. Therefore, robust and accurate methods are needed to determine arsenic speciation profiles for materials related to public health initiatives, such as food safety. Here, X
Gabriel Ycas, Fabrizio Giorgetta, Jacob T. Friedlein, Daniel Herman, Kevin Cossel, Esther Baumann, Nathan Newbury, Ian Coddington
This manuscript describes the design of a robust, mode-locked laser based, mid-infrared dual- comb spectrometer operating in the 3.1-µm to 4-µm spectral window. The design represents an improvement in signal-to-noise, system size, power consumption and
Coherent anti-Stokes Raman scattering (CARS) microscopy is a label-free chemical imaging modality capable of interrogating local molecular composition, concentration, and even orientation. In comparison to traditional Raman spectroscopy/imaging, CARS
Young Jong Lee, Shuyu Xu, Chad R. Snyder, Jeremy Rowlette
The 3D molecular orientations of polymer chains are imaged and compared for a quiescent spherulite region and a shear deformed region of a semicrystalline poly(e-caprolactone) (PCL) film. The images of 3D orientation are acquired by a newly developed
Jagannath Paul, Hendrik Rose, Ethan Swagel, Torsten Meier, Jared Wahlstrand, Alan Bristow
Multidimensional coherent spectroscopy (MDCS) is used to separate coherent and incoherent many-body contributions to the population-time dynamics in a GaAs-based semiconductor microcavity encapsulating a single InGaAs quantum well. In a three-pulse four
Steven Grantham, Thomas C. Larason, Clarence Zarobila, Stephen Maxwell, John Woodward, Kevin Turpie, S. Andrew Gadsden
The objective of the airborne LUnar Spectral Irradiance (air-LUSI) project is to make low uncertainty, SI-traceable measurements of the lunar spectral irradiance in the visible to near-infrared (VNIR) region from an aircraft above most of the optically
Eric Norrgard, Daniel Barker, Stephen Eckel, Sergey Porsev, Charles Cheung, Mikhail Kozlov, Ilya Tupitsyn, Marianna Safronova
Here we report measured and calculated values of decay rates of the 3d$^4$($^5$D)4s4p($^3$P$^\rmo}}$)\ y$^7$P$^\rmo}}_2,3,4}$ states of Cr I. The decay rates are measured using time-correlated single photon counting with roughly 1\,\% total uncertainty. In
Zhengwei Wang, Kevin O'Dwyer, Ryan Muddiman, Tomas Ward, Charles Camp, Bryan Hennelly
Rapid label-free spectroscopy of biological and chemical specimen via molecular vibration through means of Broadband Coherent Anti-Stokes Raman Scattering (B-CARS) could serve as a basis for a robust diagnostic platform for a wide range of applications. A
Csilla Szabo-Foster, James Cline, Albert Henins, Lawrence T. Hudson, Marcus Mendenhall
The NIST Vacuum Double-Crystal Spectrometer (VDCS) has been modernized and is now capable of recording reference-free wavelength-dispersive spectra in the 2 keV to 12 keV x-ray energy range. The VDCS employs crystals in which the lattice spacings are
Anisotropic molecular alignment occurs ubiquitously and often heterogeneously in three dimensions (3D). However, conventional imaging approaches based on polarization can map only molecular orientation projected onto the 2D polarization plane. Here, an
Hannes Hempel, Edwin J. Heilweil, Timothy Magnanelli
Mobilities and lifetimes of photogenerated charge carriers are core properties of photovoltaic materials and can both be characterized by contactless terahertz or microwave measurements. Previously reported values for lead-halide perovskites vary by orders