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Clarence Zarobila, Steven Grantham, Steven W. Brown, John T. Woodward IV, Stephen Maxwell, Dana R. Defibaugh, Thomas Larason, Kevin Turpie
We have designed a non-imaging telescope for measurement of the spectral irradiance of the moon. The telescope was integrated into a wing pod of a NASA ER-2 research aircraft to measure lunar spectral irradiance during flight. The telescope and support
Ari D. Feldman, Jeffrey A. Jargon, Tasshi Dennis, Paul D. Hale
We present the first-ever comparison of a photodiodes measured frequency response calibrated with an electro-optic sampling system and a heterodyne system up to 75 GHz, along with the systems respective 95% confidence intervals. A brief description of
Mark Bieler, Paul Struszewski, Ari Feldman, Jeffrey Jargon, Paul D. Hale, Pengwei Gong, Wen Xie, Chuntao Yang, Zhigang Feng, Kejia Zhao, Zhijun Yang
We report on the first international comparison in ultrafast waveform metrology. To this end, the frequency and time responses of a photodiode with a nominal bandwidth of 100 GHz have been measured by several National Metrology Institutes during the last
Robin P. Hansen, Amit K. Agrawal, Michael Shur, Jerry Tersoff, Babak Nikoobakht, Yuqin Zong
"Efficiency droop," i.e., a decline in brightness of light-emitting diodes (LEDs) at high electrical currents, limits the performance of all commercial LEDs and has limited the output power of submicrometer LEDs and lasers to nanowatts. We present a fin p
Alexander N. Tait, Sonia M. Buckley, Jeffrey M. Shainline, Adam N. McCaughan, Jeffrey T. Chiles, Sae Woo Nam, Richard P. Mirin
Superconducting optoelectronic networks could achieve scales unmatched in hardware-based neuromorphic computing. After summarizing recent progress in this area, we report new results in cryogenic silicon photonic light sources, components central to these
Alexander N. Tait, Sonia M. Buckley, Jeffrey T. Chiles, Adam N. McCaughan, Sae Woo Nam, Richard P. Mirin, Jeffrey M. Shainline
Defect centers are promising candidates for waveguide-integrated silicon light sources. We demonstrate microresonator- and waveguide-coupled photoluminescence from silicon W centers. Observations indicate that wavelengths that are on-resonance with
Jeffrey T. Chiles, Sonia M. Buckley, Adriana E. Lita, Varun B. Verma, Jeffrey M. Shainline, Richard P. Mirin, Sae Woo Nam, Jason Allmaras, Boris Korzh, Emma Wollman, Matthew Shaw
We report on the fabrication and characterization of single-photon-sensitive WSi superconducting detectors with wire widths from 1 υm to 3 υm. The devices achieve saturated internal detection efficiency at 1.55 υm wavelength and exhibit maximum count rates
Kassiopeia A. Smith, Bryan T. Bosworth, Nicholas R. Jungwirth, Jerome G. Cheron, Nathan D. Orloff, Christian J. Long, Dylan F. Williams, Richard A. Chamberlin, Franklyn J. Quinlan, Tara M. Fortier, Ari D. Feldman
A combination of on-wafer metrology and high-frequency network analysis was implemented to measure the response of transmission-line integrated Er-GaAs and InGaAs photomixers up to 1 THz to support the telecommunication and electronics industry.
Albert Davydov, Sergiy Krylyuk, Angela R. Hight Walker, Bojan R. Ilic, Andrey Krayev, Ashish Bhattarai, Alan G. Joly, Matej Velicky, Patrick Z. El-Khoury
Plasmonic tip-sample junctions, at which the incident and scattered optical fields are localized and optimally enhanced, are often exploited to achieve ultrasensitive and highly spatially localized tip-enhanced Raman scattering (TERS). Recent work has
Greg P. Smestad, Thomas Germer, Hameed Alrashidi, Eduardo F. Fern?ndez, Sumon Dey, Paidisetty S. Kumar, Honey Brahma, Aritra Ghosh, Nazmi Sellami, Ibrahim A. Hassan, Amal Kasry, Bala Pesala, S. Senthilarasu, Florencia Almonacid, K. S. Reddy, Tapas K. Mallick, Leonardo Micheli
The accumulation of soiling on photovoltaic (PV) modules affects PV systems worldwide. Soiling consists of mineral dust, soot particles, aerosols, pollen, fungi and/or other contaminants that deposit on the surface of PV modules. Soiling absorbs, scatters
Edward Garboczi, Sumitra Dey, Deb Chatterjee, Ahmed M. Hassan
Plasmonic nano-antennas are typically designed using RF-inspired parametric optimization process and/or using trial and error search algorithms which lack proper physical insight. In this study, we demonstrate how the Characteristic Mode Analysis (CMA)
Varun Verma, Adriana Lita, Sae Woo Nam, R P. Mirin, Emma Wollman, William Farr, Matthew Shaw
We present a 1024-element imaging array of superconducting nanowire single photon detectors (SNSPDs) using a 32x32 row-column multiplexing architecture. Large arrays are desirable for applications such as imaging, spectroscopy, or particle detection.
Christian Haffner, Andreas Joerg, Michael Doderer, Daniel Chelladurai, Felix Mayor, Comsin Ioan Roman, Yuriy Fedoryshyn, Mikael Mazur, Maurizio Burla, Henri J. Lezec, Vladimir A. Aksyuk, Juerg Leuthold
Reprogrammable optical networks that operate in symbiosis with CMOS electronics promise to advance technologies such as optical neural networks. However, current electro-optical switching technologies fail to combine CMOS-voltages, micrometer-scale
Brian J. Nablo, Jungjoon Ahn, Kiran Bhadriraju, Jong M. Lee, Darwin Reyes-Hernandez
We present the quantification of cell viability during neutral red (NR) uptake with a compact lens-free system utilizing two light sources. Conventionally, the NR uptake assay determines cell viability based on the accumulation of NR within lysosomes and
Jared H. Strait, Glenn E. Holland, Wenqi Zhu, Cheng Zhang, Bojan R. Ilic, Amit K. Agrawal, Domenico Pacifici, Henri J. Lezec
The photon-drag effect, the rectified current in a medium induced by conservation of momentum of absorbed or redirected light, is a unique probe of the detailed mechanisms underlying radiation pressure. We revisit this effect in gold, a canonical Drude
The irradiance spectral responsivity is an important measurement characteristic for a reference solar cell and has served as a primary reference cell calibration method for a growing number of national labs in recent years. This paper discusses the process
Alessandro Restelli, Joshua C. Bienfang, Alan L. Migdall
High-speed periodic gating of InGaAs/InP single-photon avalanche diodes (SPADs) has allowed these detectors to operate at count rates above $10^8$ per second with low-afterpulsing. However, a drawback of high-speed periodic gating is that bias gates are
Matthew Brubaker, Kristen Genter, Alexana Roshko, Paul T. Blanchard, Bryan T. Spann, Todd E. Harvey, Kris A. Bertness
Ultraviolet light-emitting diodes (UV LEDs) fabricated from N-polar AlGaN/GaN core-shell nanowires with p-i-n structure produced electroluminescence at 365 nm with 5x higher intensities than similar GaN homojunction LEDs. The improved characteristics were
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
Dianne L. Poster, Carl C. Miller, Yaw S. Obeng, Michael T. Postek, Troy E. Cowan, Richard A. Martinello
Nation-wide, healthcare-associated infections (HAIs) infect one in every 25 hospital patients, account for more than 100,000 deaths and increase medical costs by around $96-147B, each year. Ultraviolet-C (UV-C) antimicrobial devices are shown to reduce the
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
Dongheon Ha, Yohan Yoon, Ik Jae Park, Paul M. Haney, Nikolai B. Zhitenev
Photocurrent generation of methylammonium lead iodide (CH3NH3PbI3) hybrid perovskite solar cells is observed at the nanoscale using near-field scanning photocurrent microscopy (NSPM). We examine how the spatial map of photocurrent at individual grains or
Matthew D. Brubaker, Kristen L. Genter, Bryan T. Spann, Alexana Roshko, Paul T. Blanchard, Todd E. Harvey, Kristine A. Bertness
GaN nanowire LEDs with radial p-i-n junctions were grown by molecular beam epitaxy using N- polar selective area growth on Si(111) substrates. The N-polar selective area growth process facilitated the growth of isolated and high-aspect-ratio n-type NW
Ivan Ryger, Aly Artusio-Glimpse, Paul A. Williams, Gordon A. Shaw, Matt Simons, Christopher L. Holloway, John H. Lehman
We demonstrate a compact electromagnetic power sensor based on force effects of electromagnetic radiation onto a highly reflective mirror surface. Unlike the conventional power measurement approach, the photons are not absorbed and can be further used in
We introduce single layer silicon dioxide (SiO2) nanosphere arrays as antireflection coatings (ARCs) on a gallium arsenide (GaAs) solar cell. We make macro- and nanoscale experiments and finite-difference time-domain (FDTD) calculations to prove the