Optics Commons^™

Harmonic Generation In Multiresonant Plasma Films, Maria Antonietta Vincenti, Domenico De Ceglia, Joseph W. Haus, Michael Scalora

Electrical and Computer Engineering Faculty Publications

We investigate second- and third-harmonic generation in a slab of material that displays plasma resonances at the pump and its harmonic frequencies. Near-zero refractive indices and local field enhancement can deplete the pump for kW/cm² incident powers, without resorting to other resonant photonic mechanisms. We show that low-threshold, highly efficient nonlinear processes are possible in the presence of losses and phase mismatch in structures that are 10⁴ times shorter than typical nonlinear crystals, for relatively low irradiance values.

Altered Cholesterol Metabolism In Human Cancers Unraveled By Label-Free Spectroscopic Imaging, Shuhua Yue

Open Access Dissertations

Despite tremendous scientific achievements, cancer remains the second leading cause of death in the United States. Metabolic reprogramming has been increasingly recognized as a core hallmark of cancer. My dissertation work identified novel diagnostic markers and therapeutic targets for human cancers through the study of cholesterol in cancer cells.

Enabled by label-free Raman spectromicroscopy, we performed the first quantitative analysis of lipogenesis at single cell level in human patient cancerous tissues. Our imaging data revealed an unexpected, aberrant accumulation of esterified cholesterol in lipid droplets of high-grade prostate cancer and metastases, but not in normal prostate, benign prostatic hyperplasia, or …

Photon Counting Compressive Depth Mapping, Gregory A. Howland, Daniel J. Lum, Matthew R. Ware, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We demonstrate a compressed sensing, photon counting lidar system based on the single-pixel camera. Our technique recovers both depth and intensity maps from a single under-sampled set of incoherent, linear projections of a scene of interest at ultra-low light levels around 0.5 picowatts. Only two-dimensional reconstructions are required to image a three-dimensional scene. We demonstrate intensity imaging and depth mapping at 256 × 256 pixel transverse resolution with acquisition times as short as 3 seconds. We also show novelty filtering, reconstructing only the difference between two instances of a scene. Finally, we acquire 32 × 32 pixel real-time video for …

Image Deblurring And Near-Real-Time Atmospheric Seeing Estimation Through The Employment Of Convergence Of Variance, Brian J. Neff, Quentin D. Macmanus, Stephen C. Cain, Richard K. Martin

Faculty Publications

A new image reconstruction algorithm is presented that will remove the effect of atmospheric turbulence on motion compensated frame average images. The primary focus of this research was to develop a blind deconvolution technique that could be employed in a tactical military environment where both time and computational power are limited. Additionally, this technique can be employed to measure atmospheric seeing conditions. In a blind deconvolution fashion, the algorithm simultaneously computes a high resolution image and an average model for the atmospheric blur parameterized by Fried’s seeing parameter. The difference in this approach is that it does not assume a …

Technical Advantages For Weak-Value Amplification: When Less Is More, Andrew N. Jordan, Julián Martínez-Rincón, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

The technical merits of weak-value-amplification techniques are analyzed. We consider models of several different types of technical noise in an optical context and show that weak-value-amplification techniques (which only use a small fraction of the photons) compare favorably with standard techniques (which use all of them). Using the Fisher-information metric, we demonstrate that weak-value techniques can put all of the Fisher information about the detected parameter into a small portion of the events and show how this fact alone gives technical advantages. We go on to consider a time-correlated noise model and find that a Fisher-information analysis indicates that the …

Nonlinear Dynamics Of Bragg-Domain Acousto-Optic Hybrid Feedback For First-Order Scattering Of Profiled Optical Beams, Monish Ranjan Chatterjee, Fares S. Almehmadi

Electrical and Computer Engineering Faculty Publications

A series of recent studies involving hybrid acousto-optic (AO) scattering in the Bragg domain under first-order feedback have shown the ability of the AO feedback system to encrypt, transmit and decrypt RF information applied via the sound driver. The basic premise of this operation is founded on the chaotic nature of the hybrid Bragg cell under feedback.

The Carbon Rent Economics Of Climate Policy, Matthias Kalkuhl, Robert J. Brecha

Physics Faculty Publications

By reducing the demand for fossil fuels, climate policy can reduce scarcity rents for fossil resource owners. As mitigation policies ultimately aim to limit emissions, a new scarcity for “space” in the atmosphere to deposit emissions is created. The associated scarcity rent, or climate rent (that is, for example, directly visible in permit prices under an emission trading scheme) can be higher or lower than the original fossil resource rent. In this paper, we analyze analytically and numerically the impact of mitigation targets, resource availability, backstop costs, discount rates and demand parameters on fossil resource rents and the climate rent. …

Complex Reflection Coefficients Of P- And S-Polarized Light At The Pseudo-Brewster Angle Of A Dielectric–Conductor Interface, Rasheed M.A. Azzam

Electrical Engineering Faculty Publications

The complex Fresnel reflection coefficients rp and rs of p- and s-polarized light and their ratio ρ = rp/rs at the pseudo-Brewster angle (PBA) φpBof a dielectric-conductor interface are evaluated for all possible values of the complex relative dielectric function Ε = |Ε| exp(-jθ) = Εr - jΕi, Εi > 0 that share the same φpB. Complex-plane trajectories of rp, rs, and ρ at the PBA are presented at discrete values of φpB from 5° to 85° in equal steps of 5° as θ is increased from 0° to 180°. It is shown that for φpB > 70° (high-reflectance metals in the …

Weak-Values Technique For Velocity Measurements, Gerardo I. Viza, Julián Martínez-Rincón, Gregory A. Howland, Hadas Frostig, Itay Shomroni, Barak Dayan, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

In a recent Letter, Brunner and Simon proposed an interferometric scheme using imaginary weak values with a frequency-domain analysis to outperform standard interferometry in longitudinal phase shifts [Phys. Rev. Lett 105, 010405 (2010)]. Here we demonstrate an interferometric scheme combined with a time-domain analysis to measure longitudinal velocities. The technique employs the near-destructive interference of non-Fourier limited pulses, one Doppler shifted due to a moving mirror in a Michelson interferometer. We achieve a velocity measurement of 400  fm/s and show our estimator to be efficient by reaching its Cramér–Rao bound.

Characterization Of Samples For Optimization Of Infrared Stray Light Coatings, Carey L. Baxter, Rebecca Salvemini, Zaheer A. Ali, Patrick Waddell, Greg Perryman, Bob Thompson

STAR Program Research Presentations

NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) is a converted 747SP that houses a 2.5 m telescope that observes the sky through an opening in the side of the aircraft. Because it flies at altitudes up to 45,000 feet, SOFIA gets 99.99% transmission in the infrared. Multiple science instruments mount one at a time on the telescope to interpret infrared and visible light from target sources. Ball Infrared Black (BIRB) currently coats everything that the optics sees inside the telescope assembly (TA) cavity in order to eliminate noise from the glow of background sky, aircraft exhaust, and other sources. A …

Vertical Beam Size Measurements In The Spear3 Accelerator At Slac, Natalie Ann Larosa, Jeff Corbett

STAR Program Research Presentations

Synchrotron radiation is a powerful tool used in many fields of science ranging from materials characterization to structural biology. Each year thousands of scientists travel to SLAC to use high-resolution x-rays emitted from a relativistic electron beam circulating in the SPEAR3 synchrotron light source. To characterize the beam size in SPEAR3, we constructed a visible-light interferometer capable of measuring the 22um vertical beam size. The interferometer is located 17m away from the source point and consists of two vertically separated slits. Visible light emitted from the synchrotron passes through the two slits and interferes on a CCD camera to produce …

The Standard New Astronomy Cryostat For Sofia: A Design For Cryogen-Free Infrared Astronomy, Carey F. Scott, Jeffrey Van Cleve, Eric Burgh, Earl T. Daley, Ali Kashani, Zaheer Ali

STAR Program Research Presentations

Astronomy at infrared wavelengths requires optical instruments that operate at low temperatures, which is typically done using liquid cryogens such as nitrogen and helium. These cryogens are costly and limit the operational time of the science instrument. The Standard New Astronomy Cryostat for SOFIA (SNACS) will provide a design for a helium cryocooler-cooled cryostat that meets the stringent airworthiness requirements of the Stratospheric Observatory for Infrared Astronomy (SOFIA) and can be used by future instrument builders to reduce the cost and risk of their instrument design and development. The SNACS dewar will provide approximately 3.4 x 10^-1 cubic meters …

Flitecam Data Process Validation, Jesse K. Tsai, Sachindev S. Shenoy, Brent Cedric Nicklas, Zaheer Ali, William T. Reach

STAR Program Research Presentations

FLITECAM Data Processing Validation

Many of the challenges that come from working with astronomical imaging arise from the reduction of raw data into scientifically meaningful data. First Light Infrared Test CAMera (FLITECAM) is an infrared camera operating in the 1.0–5.5 μm waveband on board SOFIA (Stratospheric Observatory For Infrared Astronomy). Due to the significant noise from the atmosphere and the camera itself, astronomers have developed many methods to reduce the effects of atmospheric and instrumental emission. The FLITECAM Data Reduction Program (FDRP) is a program, developed at SOFIA Science Center, subtracts darks, removes flats, and dithers images.

This project contains …

Investigation Of Negative Index In Dispersive, Chiral Materials Via Contra-Propagating Velocities Under Second-Order Dispersion (Gvd), Monish Ranjan Chatterjee, Tarig A. Algadey

Electrical and Computer Engineering Faculty Publications

Negative refractive index arises typically in metamaterials via multiple routes. One such avenue is the condition where the Poynting vector of the electromagnetic wave is in opposition to the group velocity in the material. An earlier work along this route in a chiral material led to the well-known result of requiring very large (non-realizable) chirality.

Thereafter, a combination of chirality together with first-order dispersion was examined using plane wave electromagnetic analysis. To arrive at the conclusions in that approach, the three wave velocities (energy, group and phase) were derived under first-order dispersion in permittivity, permeability and chirality. Negative index in …

Numerical Examination Of Acousto-Optic Bragg Interactions For Profiled Lightwaves Using A Transfer Function Formalism, Monish Ranjan Chatterjee, Fares S. Almehmadi

Electrical and Computer Engineering Faculty Publications

Classically, acousto-optic (AO) interactions comprise scattering of photons by energetic phonons into higher and lower orders. Standard weak interaction theory describes diffraction in the Bragg regime as the propagation of a uniform plane wave of light through a uniform plane wave of sound, resulting in the well-known first- and zeroth-order diffraction.

Our preliminary investigation of the nature of wave diffraction and photon scattering from a Bragg cell under intensity feedback with profiled light beams indicates that the diffracted (upshifted photon) light continues to maintain the expected (uniform plane wave) behavior versus the optical phase shift in the cell within a …

Adaptive Wiener Filter Super-Resolution Of Color Filter Array Images, Barry K. Karch, Russell C. Hardie

Electrical and Computer Engineering Faculty Publications

Digital color cameras using a single detector array with a Bayer color filter array (CFA) require interpolation or demosaicing to estimate missing color information and provide full-color images. However, demosaicing does not specifically address fundamental undersampling and aliasing inherent in typical camera designs. Fast non-uniform interpolation based super-resolution (SR) is an attractive approach to reduce or eliminate aliasing and its relatively low computational load is amenable to real-time applications. The adaptive Wiener filter (AWF) SR algorithm was initially developed for grayscale imaging and has not previously been applied to color SR demosaicing. Here, we develop a novel fast SR method …

Designing A Cold Source To Be Integrated With The Existing Telescope Assembly Alignment Simulator, Rebecca L. Salvemini, Carey Baxter, Zaheer Ali, Greg Perryman, Robert Thompson, Daniel Nolan

STAR Program Research Presentations

The stratospheric observatory for infrared astronomy (SOFIA), is a modified Boeing 747-SP with a 2.5m telescope mounted inside. SOFIA flies at an altitude of 45,000 feet, above 99% of the water vapor in the atmosphere, allowing transmission of most infrared radiation. SOFIA has seven different science instruments (SI) that can be used to collect astronomical data, enabling scientists to look at many different wavelengths of infrared and visible radiation.

Optical And Thermal Properties Of Spinel With Revised (Increased) Absorption At 4 To 5 Μm Wavelengths And Comparison With Sapphire, Daniel C. Harris, Giorgio Turri

Publications

Infrared absorption of high-quality, commercial, polycrystalline MgAl2O4 spinel is ∼40% greater in the range of 3.8 to 5.0 μm than the value predicted by the computer code OPTIMATR®, which has been used for window and dome design for more than 20 years. As a result, spinel and a-plane sapphire windows designed to support the same external pressure with the same probability of survival have approximately the same infrared absorptance in the range 3.8 to 5.0 μm. c-Plane sapphire has greater absorptance than spinel in the range 3.8 to 5.0 μm. Spinel has two weak absorption bands near 1.8 and 3.0 …

High-Performance, Scalable Optical Network-On-Chip Architectures, Xianfang Tan

UNLV Theses, Dissertations, Professional Papers, and Capstones

The rapid advance of technology enables a large number of processing cores to be integrated into a single chip which is called a Chip Multiprocessor (CMP) or a Multiprocessor System-on-Chip (MPSoC) design. The on-chip interconnection network, which is the communication infrastructure for these processing cores, plays a central role in a many-core system. With the continuously increasing complexity of many-core systems, traditional metallic wired electronic networks-on-chip (NoC) became a bottleneck because of the unbearable latency in data transmission and extremely high energy consumption on chip. Optical networks-on-chip (ONoC) has been proposed as a promising alternative paradigm for electronic NoC with …

All-Optical Sigma-Delta Modulator For Analog-To-Digital Conversion, Bin Zhang

Graduate Theses - Physics and Optical Engineering

In this thesis, an all-optical sigma-delta (ΣΔ) modulator for analog-to-digital conversion (ADC) using a novel optical bistable switch, the SOA-PD device, is demonstrated. The presented all-optical ΣΔ modulator consists of a photonic leaky integrator, the SOA-PD optical comparator, and a positive feedback loop. The switching properties of the SOA-PD device are studied and experimentally tested to confirm its performance. Then the all-optical ΣΔ modulator is designed according to the switching performance of the SOA-PD device. It is demonstrated that the all-optical ΣΔ modulator is capable of producing an inverted non-return-to-zero (NRZ) type binary output for frequencies in the range of …

Design And Study Of Acrylamide-Based Photopolymer Holographic Optical Elements For Solar Application, Hoda Akbari, Izabela Naydenova, Manus Kennedy, John Doran, Suzanne Martin

Conference Papers

Abstract: Solar concentrators can be used to reduce the cost of photovoltaic electrical power generation by collecting incident solar radiation from a given aperture area and transmitting the energy to a reduced area. In doing so, the overall cost of power (Wp) can be reduced as less area of photovoltaic is required. This paper will discuss Holographic Solar Concentrators fabricated in an acrylamide photopolymer , describing the optical recording process and showing how the fabricated HOE’s can be used in solar concentrator devices. Preliminary lifetime studies are also discussed.

Einstein-Podolsky-Rosen Steering Inequalities From Entropic Uncertainty Relations, James Schneeloch, Curtis J. Broadbent, Stephen P. Walborn, Eric G. Cavalcanti, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

We use entropic uncertainty relations to formulate inequalities that witness Einstein-Podolsky-Rosen (EPR)-steering correlations in diverse quantum systems. We then use these inequalities to formulate symmetric EPR-steering inequalities using the mutual information. We explore the differing natures of the correlations captured by one-way and symmetric steering inequalities and examine the possibility of exclusive one-way steerability in two-qubit states. Furthermore, we show that steering inequalities can be extended to generalized positive operator-valued measures, and we also derive hybrid steering inequalities between alternate degrees of freedom.

Clustering Hyperspectral Imagery For Improved Adaptive Matched Filter Performance, Jason P. Williams, Kenneth W. Bauer, Mark A. Friend

Faculty Publications

This paper offers improvements to adaptive matched filter (AMF) performance by addressing correlation and non-homogeneity problems inherent to hyperspectral imagery (HSI). The estimation of the mean vector and covariance matrix of the background should be calculated using “target-free” data. This statement reflects the difficulty that including target data in estimates of the mean vector and covariance matrix of the background could entail. This data could act as statistical outliers and severely contaminate the estimators. This fact serves as the impetus for a 2-stage process: First, attempt to remove the target data from the background by way of the employment of …

Development Without Energy? Assessing Future Scenarios Of Energy Consumption In Developing Countries, Jan Christof Steckel, Robert J. Brecha, Michael Jakob, Jessica Strefler, Gunnar Luderer

Physics Faculty Publications

We analyze the relationship between economic development and energy consumption in the context of greenhouse gas mitigation. The main contribution of this work is to compare estimates of energy thresholds in the form of minimum energy requirements to reach high levels of development with output projections of per capita final energy supply from a group of integrated assessment models (IAMs). Scenarios project that reductions of carbon emissions in developing countries will be achieved not only by means of decreasing the carbon intensity, but also by making a significant break with the historically observed relationship between energy use and economic growth. …

Measuring The Refractive Index Of Infrared Materials By Dual-Wavelength Fabry-Perot Interferometry, Griffin Taylor

Physics

No abstract provided.

Raman Spectroscopic Analysis Of Human Skin Tissue Sections Ex-Vivo: Evaluation Of The Effects Of Tissue Processing And Dewaxing, Syed Mehmood Ali, Franck Bonnier, Ali Tfayli, Helen Lambkin, Kathleen Flynn, Vincent Mcdonagh, Claragh Healy, Thomas Lee, Fiona Lyng, Hugh Byrne

Articles

Raman spectroscopy coupled with K-means clustering analysis (KMCA) is employed to elucidate the biochemical structure of human skin tissue sections, and the effects of tissue processing. Both hand and thigh sections of human cadavers were analysed in their unprocessed and formalin fixed paraffin processed (FFPP) and subsequently dewaxed forms. In unprocessed sections, KMCA reveals clear differentiation of the stratum corneum, intermediate underlying epithelium and dermal layers for sections from both anatomical sites. The stratum corneum is seen to be relatively rich in lipidic content; the spectrum of the subjacent layers is strongly influenced by the presence of melanin, while that …

Modeling A Sensor To Improve Its Efficacy, Nabin K. Malakar, Daniil Gladkov, Kevin H. Knuth

Physics Faculty Scholarship

Robots rely on sensors to provide them with information about their surroundings. However, high-quality sensors can be extremely expensive and cost-prohibitive. Thus many robotic systems must make due with lower-quality sensors. Here we demonstrate via a case study how modeling a sensor can improve its efficacy when employed within a Bayesian inferential framework. As a test bed we employ a robotic arm that is designed to autonomously take its own measurements using an inexpensive LEGO light sensor to estimate the position and radius of a white circle on a black field. The light sensor integrates the light arriving from a …

Nanowire Metal-Insulator-Metal Plasmonic Devices, Joseph W. Haus, Li Li, Cong Deng, Nkorni Katte, Michael Scalora, Domenico De Ceglia, Maria Antonietta Vincenti

Electro-Optics and Photonics Faculty Publications

In this paper we theoretically study the responsivity of Metal-Insulator-Metal nanostructures to light illumination over a broad wavelength band (1 - 25 microns) and we examine the role of a local field enhancement and electrostatic field on the responsivity.

A Gamos Plug-In For Geant4 Based Monte Carlo Simulation Of Radiation-Induced Light Transport In Biological Media, Adam K. Glaser, Stephen C. Kanick, Rongxiao Zhang, Pedro Arce, Brian W. Pogue

Dartmouth Scholarship

We describe a tissue optics plug-in that interfaces with the GEANT4/GAMOS Monte Carlo (MC) architecture, providing a means of simulating radiation-induced light transport in biological media for the first time. Specifically, we focus on the simulation of light transport due to the Čerenkov effect (light emission from charged particle's traveling faster than the local speed of light in a given medium), a phenomenon which requires accurate modeling of both the high energy particle and subsequent optical photon transport, a dynamic coupled process that is not well-described by any current MC framework. The results of validation simulations show excellent agreement with …

The Geometry And Sensitivity Of Ion-Beam Sculpted Nanopores For Single Molecule Dna Analysis, Ryan Connor Rollings

Graduate Theses and Dissertations

In this dissertation, the relationship between the geometry of ion-beam sculpted solid-state nanopores and their ability to analyze single DNA molecules using resistive pulse sensing is investigated. To accomplish this, the three dimensional shape of the nanopore is determined using energy filtered and tomographic transmission electron microscopy. It is shown that this information enables the prediction of the ionic current passing through a voltage biased nanopore and improves the prediction of the magnitude of current drop signals when the nanopore interacts with single DNA molecules. The dimensional stability of nanopores in solution is monitored using this information and is improved …