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Dimitar Popmintchev, Benjamin Galloway, Ming-Chang Chen, Franklin Dolar, Christopher Mancuso, Amelia Hankla, Luis Miaja Avila, Galen O'Neil, Guangyu Fan, Skirmantas Alisauskas, Giedrius Andriukaitis, Tadas Balciunas, Oliver M?cke, Audrius Pugzlys, Andrius Baltuska, Henry C. Kapteyn, Tenio Popmintchev, Margaret M. Murnane
Phase matching of the high-order harmonic generation process now makes it possible to produce spatially and temporally coherent ultrafast X-ray beams, with bandwidths spanning more than 12 octaves, from the UV to the keV region. Here we report the first
Quantum mechanics allows measurements that surpass the fundamental sensitivity limits of classical methods. To benefit from the quantum advantage in a practical setting, the receiver should use communication channel resources optimally; this can be done
Kaitlin Wozniak, Thomas Germer, Sam Butler, Daniel Brooks, Krystel Huxlin, Jonathan D. Ellis
We present measurements of light scatter induced by a new ultrafast laser technique being developed for laser refractive correction in transparent ophthalmic materials such as cornea, contact lenses, and/or intraocular lenses. In this new technique, called
John H. Lehman, Christopher S. Yung, Nathan A. Tomlin, Davis R. Conklin, Michelle S. Stephens
It has been shown that coatings comprised of carbon nanotubes are very black; that is, characterized by low reflectance over a broad wavelength range from the visible to far infrared. Arguably there is no other material that is comparable. This is
Nanoscale surface patterning commonly used to increase absorption of solar cells can adversely impact the open-circuit voltage due to increased surface area and recombination. Here, we demonstrate absorptivity and photocurrent enhancement using silicon
Michael G. Huber, Muhammad D. Arif, Thomas H. Gnaupel-Herold, Michelle E. Jamer, Ben Heacock, David G. Cory, R. Haun, Joachim Nsofini, Dimitry A. Pushin, Ivar Taminiau, A.R. Young
We find that annealing a previously chemically etched interferometer at 800 °C dramatically increased the interference fringe visibility from 23 % to 90 %. The Bragg plane misalignments were also measured before and after annealing using neutron rocking
Ross N. Andrews, Suresh Narayanan, Fan Zhang, Ivan Kuzmenko, Jan Ilavsky
X-ray photon correlation spectroscopy (XPCS), as an extension of dynamic light scattering (DLS) in the X-ray regime, detects temporal intensity fluctuations of coherent speckles and provides scattering vector-dependent sample dynamics at smaller length
Laura C. Sinclair, Hugo Bergeron, William C. Swann, Jean-Daniel Deschenes, Nathan R. Newbury
We demonstrate carrier-phase optical two-way time-frequency transfer (carrier-phase OTWTFT) across a turbulent air path. Through the two-way exchange of optical pulse trains from phase- stabilized frequency combs, carrier-phase OTWTFT continuously tracks
Paul Lemaillet, Catherine C. Cooksey, Jeeseong Hwang, Heidrun Wabnitz, Dirk Grosenick, Lin Yang, David W. Allen
We present broadband measurements of the optical properties of tissue-mimicking solid phantoms using a single integrating sphere to measure the hemispherical reflectance and transmittance under a direct illumination at the normal incident angle. These
Photothermal induced resonance (PTIR) is a scanning probe technique that provides sample composition information with a lateral resolution down to 20 nm. Interest in PTIR stems from its ability to identify unknown samples at the nanoscale thanks, in first
Ultrafast pulsed laser interferometry (PLI) can measure picometer displacements at sub- nanosecond time scales, such as acoustic waves and vibrations in microstructures. In this letter, the effects of pulse characteristics on the accuracy of PLI are
Joshua A. Gordon, Christopher L. Holloway, Matthew T. Simons
We present a technique which shows great promise for realizing an atomic standard measurement of RF fields that is intrinsically calibrated, directly linked to the SI and atomic structural constants. This technique relies on the reponse of Rydberg atoms to
Guillaume Fischer, Etienne Drahi, Martin Foldyna, Thomas Germer, Erik V. Johnson
Using a plasma to generate a surface texture with feature sizes on the order of nanometers ("nanotexturing") is a promising technique being considered for application in thin, high- efficiency crystalline silicon solar cells. This study investigates the
William R. McGehee, Thomas Michels, Vladimir A. Aksyuk, Jabez J. McClelland
We report 2D imaging of the optical mode intensity of silicon microdisk resonators using a pulsed, low-energy focused ion beam of Li+. The ion beam locally modifies the resonator structure, causing temporally varying spectroscopic shifts of the optical
Jared K. Wahlstrand, Anand Bahl, Sina Zahedpour, H M. Milchberg, Miroslav Kolesik
The nonlinear polarization response and plasma generation in noble gases produced by high- intensity optical pulses, modeled by the metastable electronic state approach, are verified against three-dimensional, space-and-time resolved measurements with
Jay H. Hendricks, Karl Jousten, Jack A. Stone Jr., Patrick F. Egan, Tom Rubin, Christof Gaiser, Rene Schodel, James A. Fedchak, Jacob E. Ricker, Jens Fluegge, Stephen P. Eckel, Julia K. Scherschligt, Daniel S. Barker, Kevin O. Douglass, Gregory F. Strouse, Uwe Sterr, Waldimir Sabuga
Since the beginning of measurement of pressure in the 17th century, the unit of pressure has been defined by the relationship of force per unit area. The present state of optical technology now offers the possibility of using a thermodynamic definition
Richelle H. Streater, Anne-Michelle R. Lieberson, Adam L. Pintar, Zachary H. Levine
The MCML program for Monte Carlo modeling of light transport in multi-layered tissues has been widely used in the past 20 years or so. Here, we have re-implemented MCML for solving the inverse problem. Our formulation features optimizing the profile log
Thomas A. Germer, Katelynn A. Sharma, Thomas G. Brown, James B. Oliver
We extend the theory of Kassam et al. [J. Opt. Soc. Am. A 12, 2009-2021 (1995)] for scattering by oblique columnar structure thin films to include the induced form birefringence and the propagation of radiation in those films. We generalize the 4 x 4
Wenqi Zhu, Ting Xu, Haozhu Wang, Cheng Zhang, Parag B. Deotare, Amit K. Agrawal, Henri J. Lezec
Recent years have witnessed growing interest in the development of lasers with small footprint for their potential applications in small-volume sensing and on-chip optical communications. Surface-plasmons electromagnetic modes evanescently confined to
The United States Geological Survey (USGS) has developed an empirical model, known as the Robotic Lunar Observatory (ROLO) Model, that predicts the reflectance of the Moon for any Sun-sensor-Moon configuration over the spectral range from 350 nm to 2500 nm
Sonia M. Buckley, Jeffrey T. Chiles, Adam N. McCaughan, Galan Moody, Kevin L. Silverman, Martin J. Stevens, Richard P. Mirin, Sae Woo Nam, Jeffrey M. Shainline
An on-chip, silicon-compatible light source has long been pursued for telecommunications, with limited success. However, for integrated systems utilizing superconducting detectors, cryogenic operation is already required. This allows these systems to
Michael Ondrusek, Veronica P. Lance, Menghua Wang, Charles Kovach, Wesley Goode, Alex Gilerson, Sam Ahmed, Ahmed El-Habashi, Robert Foster, Matteo Ottaviani, Joaquim I. Goes, Helga de Rosario Gomes, Kali McKee, Joo Won Kang, Chuanmin Hu, Jennifer Cannizzaro, Shaojie Sun, David English, B. Carol Johnson, Zhongping Lee, Junfang Lin, Nicholas Tufillaro, Ivan Lalovic, Jasmine Nahorniak, Curtiss Davis, Mike Twardowski, Nicole Stockley, Kenneth Voss
The overall aim of the annual National Oceanic and Atmospheric Administration (NOAA) dedicated Joint Polar Satellite System (JPSS) Visible Infrared Imaging Radiometer Suite (VIIRS) ocean color calibration/validation (cal/val) cruises is to support
Josue Davila-Rodriguez, Holly Leopardi, Tara Fortier, Xiaojun Xie, Joe C. Campbell, James Booth, Nate Orloff, Scott Diddams, Franklyn Quinlan
We present an experimental study of the nonlinearity of modified uni-traveling carrier (MUTC) photodiodes at cryogenic temperatures. At 120 K, the amplitudeto-phase (AM-to-PM) conversion nonlinearity is reduced by up to 10 dB, resulting in nearly 40 dB AM
Yohan Yoon, Jungseok Chae, Aaron M. Katzenmeyer, Heayoung Yoon, Joshua D. Schumacher, Sang M. An, Andrea Centrone, Nikolai B. Zhitenev
Polycrystalline thin film technology has shown great promise for low cost, high efficiency photovoltaics. To further increase the power efficiency, a firm understanding of microstructural properties of the devices is required. In this work, we investigate