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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
We demonstrate the precision molecular spectroscopy of H13CN using a free-running, all-fiber dual electro-optic frequency comb system. Successive interferograms, acquired at a rate of Δfrep = 1 MHz, were phase-corrected in post-processing, averaged, and
The demand for lightweight, cost-effective, and/or flexible electronic and optoelectronic devices drives research toward new materials advancing the desired functionality or reducing manufacturing costs. Paper, being in addition an earth abundant and
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
Electronic interactions in low-dimensional nanomaterial heterostructures can lead to novel optical response arising from exciton delocalization over the constituent materials. Similar phenomena have been suggested to arise between closely interacting
Measurements of plasma electric fields are essential to the advancement of plasma science and applications. Methods for non-invasive in situ measurements of plasma fields on micrometre length scales with high sensitivity over a large field range remain an
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