Open Access. Powered by Scholars. Published by Universities.®

Electromagnetics and Photonics Commons

Open Access. Powered by Scholars. Published by Universities.®

2018 Full-Text Articles 2890 Authors 426342 Downloads 56 Institutions

All Articles in Electromagnetics and Photonics

Faceted Search

2018 full-text articles. Page 7 of 57.

Multi-Physics Modeling, Ahmadreza Ghahremani 2016 University of Tennessee, Knoxville

Multi-Physics Modeling, Ahmadreza Ghahremani

Doctoral Dissertations

Having access to powerful processors allows scientists to carry out aggressive numerical computations to bridge the gaps which already exist among different fields of physics by exploring new multi-physics models to approach real life models of various phenomena happening around us in real life and accounting of the various coupling and dependence between the various physical parameters and material parameters.

Scientists greatly appreciate multi-physics modeling as they recognize:

1- Prototyping is expensive

2- Most of available CAD tools are not addressing the real model or accounting between the different physical parameters

3- Some difficulties to optimize the real model without ...


Chiral Light Intrinsically Couples To Extrinsic/Pseudo-Chiral Metasurfaces Made Of Tilted Gold Nanowires, Alessandro Belardini, Marco Centini, Grigore Leahu, David C. Hooper, Roberto Li Voti, Eugenio Fazio, Joseph W. Haus, Andrew Sarangan, Ventsislav K. Valev, Concita Sibilia 2016 Sapienza Università di Roma

Chiral Light Intrinsically Couples To Extrinsic/Pseudo-Chiral Metasurfaces Made Of Tilted Gold Nanowires, Alessandro Belardini, Marco Centini, Grigore Leahu, David C. Hooper, Roberto Li Voti, Eugenio Fazio, Joseph W. Haus, Andrew Sarangan, Ventsislav K. Valev, Concita Sibilia

Electro-Optics and Photonics Faculty Publications

Extrinsic or pseudo-chiral (meta)surfaces have an achiral structure, yet they can give rise to circular dichroism when the experiment itself becomes chiral. Although these surfaces are known to yield differences in reflected and transmitted circularly polarized light, the exact mechanism of the interaction has never been directly demonstrated. Here we present a comprehensive linear and nonlinear optical investigation of a metasurface composed of tilted gold nanowires. In the linear regime, we directly demonstrate the selective absorption of circularly polarised light depending on the orientation of the metasurface. In the nonlinear regime, we demonstrate for the first time how second ...


Single-Mode Optical Waveguides On Native High-Refractive-Index Substrates, Richard R. Grote, Lee C. Bassett 2016 University of Pennsylvania

Single-Mode Optical Waveguides On Native High-Refractive-Index Substrates, Richard R. Grote, Lee C. Bassett

Departmental Papers (ESE)

High-refractive-index semiconductor optical waveguides form the basis for modern photonic integrated circuits (PICs). However, conventional methods for achieving optical confinement require a thick lower-refractive-index support layer that impedes large-scale co-integration with electronics and limits the materials on which PICs can be fabricated. To address this challenge, we present a general architecture for single-mode waveguides that confine light in a high-refractive-index material on a native substrate. The waveguide consists of a high-aspect-ratio fin of the guiding material surrounded by lower-refractive-index dielectrics and is compatible with standard top-down fabrication techniques. This letter describes a physically intuitive, semi-analytical, effective index model for designing ...


Modeling And Simulation Of 1700 V 8 A Genesic Superjunction Transistor, Staci E. Brooks 2016 University of Arkansas, Fayetteville

Modeling And Simulation Of 1700 V 8 A Genesic Superjunction Transistor, Staci E. Brooks

Theses and Dissertations

The first-ever 1.7kV 8A SiC physics-based compact SPICE model is developed for behavior prediction, modeling and simulation of the GeneSiC “Super” Junction Transistor. The model implements Gummel-Poon based equations and adds a quasi-saturation collector series resistance representation from a 1.2 kV, 6 A SiC bipolar junction transistor model developed in Hangzhou, China. The model has been validated with the GA08JT17-247 device data representing both static and dynamic characteristics from GeneSiC. Parameter extraction was performed in IC-CAP and results include plots showing output characteristics, capacitance versus voltage (C-V), and switching characteristics for 25 °C, 125 °C, and 175 °C ...


Volume Holographic Recording And Readout For 90-Deg Geometry, Partha P. Banerjee, Monish Ranjan Chatterjee, Nickolai Kukhtarev, Tatiana Kukhtareva 2016 University of Dayton

Volume Holographic Recording And Readout For 90-Deg Geometry, Partha P. Banerjee, Monish Ranjan Chatterjee, Nickolai Kukhtarev, Tatiana Kukhtareva

Monish R. Chatterjee

When a prerecorded cross-beam hologram is reconstructed (so-called edge-lit readout) with a uniform plane wave and a point source, the resulting exact solutions reveal Bessel-function-type diffracted beam profiles, which are fundamentally modified under weak propagational diffraction. The case of a profiled beam readout with propagational diffraction may be analyzed using a transfer function approach based on 2-D Laplace transforms. In a second series of investigations, dynamic readout from a cross-beam volume hologram recorded with two orthogonal uniform plane waves is considered for various dependences of the refractive index modulation with intensity. Typically, refractive index profiles that are proportional to the ...


Nanofabrication And Spectroscopy Of Magnetic Nanostructures Using A Focused Ion Beam, Ali Hadjikhani 2016 FIU

Nanofabrication And Spectroscopy Of Magnetic Nanostructures Using A Focused Ion Beam, Ali Hadjikhani

FIU Electronic Theses and Dissertations

This research used a focused ion beam in order to fabricate record small nano-magnetic structures, investigate the properties of magnetic materials in the rarely studied range of nanometer size, and exploit their extraordinary characteristics in medicine and nano-electronics. This study consists of two parts: (i) Fabrication and study of record small magnetic tunnel junctions (ii) Introduction of a novel method for detection of magnetoelectric nanoparticles (MENs) in the tissue.

A key challenge in further scaling of CMOS devices is being able to perform non-volatile logic with near zero power consumption. Sub-10-nm nanomagnetic spin transfer torque (STT) magnetic tunneling junctions (MTJs ...


Sonochemical Synthesis Of Zinc Oxide Nanostructures For Sensing And Energy Harvesting, Phani Kiran Vabbina 2016 Department of Electrical and Computer Engineering, Florida International University

Sonochemical Synthesis Of Zinc Oxide Nanostructures For Sensing And Energy Harvesting, Phani Kiran Vabbina

FIU Electronic Theses and Dissertations

Semiconductor nanostructures have attracted considerable research interest due to their unique physical and chemical properties at nanoscale which open new frontiers for applications in electronics and sensing. Zinc oxide nanostructures with a wide range of applications, especially in optoelectronic devices and bio sensing, have been the focus of research over the past few decades. However ZnO nanostructures have failed to penetrate the market as they were expected to, a few years ago. The two main reasons widely recognized as bottleneck for ZnO nanostructures are (1) Synthesis technique which is fast, economical, and environmentally benign which would allow the growth on ...


Recursive Non-Local Means Filter For Video Denoising With Poisson-Gaussian Noise, Redha A. Almahdi, Russell C. Hardie 2016 University of Dayton

Recursive Non-Local Means Filter For Video Denoising With Poisson-Gaussian Noise, Redha A. Almahdi, Russell C. Hardie

Electrical and Computer Engineering Faculty Publications

In this paper, we describe a new recursive Non-Local means (RNLM) algorithm for video denoising that has been developed by the current authors. Furthermore, we extend this work by incorporating a Poisson-Gaussian noise model. Our new RNLM method provides a computationally efficient means for video denoising, and yields improved performance compared with the single frame NLM and BM3D benchmarks methods. Non-Local means (NLM) based methods of denoising have been applied successfully in various image and video sequence denoising applications. However, direct extension of this method from 2D to 3D for video processing can be computationally demanding. The RNLM approach takes ...


Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay 2016 University of Dayton

Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay

Electrical and Computer Engineering Faculty Publications

Lung cancer is the leading cause of cancer death in the United States. It usually exhibits its presence with the formation of pulmonary nodules. Nodules are round or oval-shaped growth present in the lung. Computed Tomography (CT) scans are used by radiologists to detect such nodules. Computer Aided Detection (CAD) of such nodules would aid in providing a second opinion to the radiologists and would be of valuable help in lung cancer screening. In this research, we study various feature selection methods for the CAD system framework proposed in FlyerScan. Algorithmic steps of FlyerScan include (i) local contrast enhancement (ii ...


Phase Gradient Algorithm Method For 3-D Holographic Ladar Imaging, Jason W. Stafford, Bradley D. Duncan, David J. Rabb 2016 University of Dayton

Phase Gradient Algorithm Method For 3-D Holographic Ladar Imaging, Jason W. Stafford, Bradley D. Duncan, David J. Rabb

Electro-Optics and Photonics Faculty Publications

3-D holographic ladar uses digital holography with frequency diversity to add the ability to resolve targets in range. A key challenge is that since individual frequency samples are not recorded simultaneously, differential phase aberrations may exist between them making it difficult to achieve range compression. We describe steps specific to this modality so that phase gradient algorithms (PGA) can be applied to 3-D holographic ladar data for phase corrections across multiple temporal frequency samples. Substantial improvement of range compression is demonstrated with a laboratory experiment where our modified PGA technique is applied. Additionally, the PGA estimator is demonstrated to be ...


Blind X-Ray Ct Image Reconstruction From Polychromatic Poisson Measurements, Renliang Gu, Aleksandar Dogandžić 2016 Iowa State University

Blind X-Ray Ct Image Reconstruction From Polychromatic Poisson Measurements, Renliang Gu, Aleksandar Dogandžić

Electrical and Computer Engineering Publications

We develop a framework for reconstructing images that are sparse in an appropriate transform domain from polychromatic computed tomography (CT) measurements under the blind scenario where the material of the inspected object and incident-energy spectrum are unknown. Assuming that the object that we wish to reconstruct consists of a single material, we obtain a parsimonious measurement-model parameterization by changing the integral variable from photon energy to mass attenuation, which allows us to combine the variations brought by the unknown incident spectrum and mass attenuation into a single unknown mass-attenuation spectrum function; the resulting measurement equation has the Laplaceintegral form. The ...


Analysis Of Electromagnetic Launcher Design And Modeling, Garrett Ross Germany 2016 California Polytechnic State University, San Luis Obispo

Analysis Of Electromagnetic Launcher Design And Modeling, Garrett Ross Germany

Master's Theses and Project Reports

This thesis derives working expressions from electromagnetic physical laws to gain a deeper understanding of the nature of railguns. The expressions are refined for ease of use and then compared to electromagnetic simulators that solve complex equations that arise from different rail geometry. Further simplifications lead to an expression for the final velocity of the projectile and showcase the importance of the system resistance to projectile flux gain ratio. A Simulink simulation then incorporates the resulting non-linear differential equations and approximates the projectile velocity over time based on physical dimensions and material properties. Some equations derived can be found in ...


Hall Effect Modeling In Fem Simulators And Comparison To Experimental Results In Silicon And Printed Sensors, Leonardo A. Frem 2016 California Polytechnic State University, San Luis Obispo

Hall Effect Modeling In Fem Simulators And Comparison To Experimental Results In Silicon And Printed Sensors, Leonardo A. Frem

Master's Theses and Project Reports

Finite element method simulation models for thin-film semiconductor-based Hall sensors were developed using secondary data in order to understand their behavior under strong magnetic fields. Given a device geometry and charge carrier density and mobility, the models accurately calculated sensor resistance, Hall voltage under a normally-incident constant magnetic field, and expected offset from a population of Hall devices. The model was successfully matched against data from integrated chip Hall sensors from St. Jude Medical. Additionally, the feasibility of creating Hall effect devices with common carbon ink was explored experimentally. The material properties obtained from testing these ink-based devices through the ...


Wavelength Accuracy Study For High-Density Fiber Bragg Grating Sensor Systems Using A Rapidly-Swept Akinetic-Laser Source, Jacob Egorov 2016 Cal Poly San Luis Obispo

Wavelength Accuracy Study For High-Density Fiber Bragg Grating Sensor Systems Using A Rapidly-Swept Akinetic-Laser Source, Jacob Egorov

Master's Theses and Project Reports

This thesis studies the center wavelength accuracy of a Fiber Bragg Grating Sensor system that has a large number of sensor elements both as a function of wavelength and as a function of position. Determining the center wavelength of each of the fiber optic sensors is a critical parameter that ultimately determines sensor accuracy. The high density environment can result in degradation of accuracy of the center wavelength measurement. This thesis aims to quantify this measurement error both with theoretical and experimental studies.

There are many sensing applications where optical fiber sensors are preferred over electrical sensors, such as the ...


Physics-Based Imaging Methods For Terahertz Nondestructive Evaluation Applications, Gabriel Paul Kniffin 2016 Portland State University

Physics-Based Imaging Methods For Terahertz Nondestructive Evaluation Applications, Gabriel Paul Kniffin

Dissertations and Theses

Lying between the microwave and far infrared (IR) regions, the "terahertz gap" is a relatively unexplored frequency band in the electromagnetic spectrum that exhibits a unique combination of properties from its neighbors. Like in IR, many materials have characteristic absorption spectra in the terahertz (THz) band, facilitating the spectroscopic "fingerprinting" of compounds such as drugs and explosives. In addition, non-polar dielectric materials such as clothing, paper, and plastic are transparent to THz, just as they are to microwaves and millimeter waves. These factors, combined with sub-millimeter wavelengths and non-ionizing energy levels, makes sensing in the THz band uniquely suited for ...


Histogram Of Oriented Phase (Hop): A New Descriptor Based On Phase Congruency, Hussin Ragb, Vijayan K. Asari 2016 University of Dayton

Histogram Of Oriented Phase (Hop): A New Descriptor Based On Phase Congruency, Hussin Ragb, Vijayan K. Asari

Electrical and Computer Engineering Faculty Publications

In this paper we present a low level image descriptor called Histogram of Oriented Phase based on phase congruency concept and the Principal Component Analysis (PCA). Since the phase of the signal conveys more information regarding signal structure than the magnitude, the proposed descriptor can precisely identify and localize image features over the gradient based techniques, especially in the regions affected by illumination changes. The proposed features can be formed by extracting the phase congruency information for each pixel in the image with respect to its neighborhood. Histograms of the phase congruency values of the local regions in the image ...


Investigation Of Optical Properties Of Zinc Oxide Photodetector, Tyler Chism 2016 University of Arkansas, Fayetteville

Investigation Of Optical Properties Of Zinc Oxide Photodetector, Tyler Chism

Theses and Dissertations

UV photodetection devices have many important applications for uses in biological detection, gas sensing, weaponry detection, fire detection, chemical analysis, and many others. Today’s photodetectors often utilize semiconductors such as GaAs to achieve high responsivity and sensitivity. Zinc oxide, unlike many other semiconductors, is cheap, abundant, non-toxic, and easy to grow different morphologies at the micro and nano scale. With the proliferation of these devices also comes the impending need to further study optics and photonics in relation to phononics and plasmonics, and the general principles underlying the interaction of photons with solid state matter and, specifically, semiconductors. For ...


Role Of Diffusive, Photovoltaic, And Thermal Effects In Beam Fanning In Linbo3, Jaw-Jueh Liu, Partha P. Banerjee, Q. W. Song 2016 University of Alabama, Huntsville

Role Of Diffusive, Photovoltaic, And Thermal Effects In Beam Fanning In Linbo3, Jaw-Jueh Liu, Partha P. Banerjee, Q. W. Song

Partha Banerjee

We analyze the steady-state (Gaussian) beam fanning in LiNbO3 from the nonlinearly coupled Kukhtarev equations by including both diffusive and photovoltaic effects and by adding the thermal effect in the calculation. There is good agreement between theory and experiment. The results show a symmetric beam-fanning pattern whose size depends on the beam waist and the power. Possible applications of our results in nondestructive testing of material parameters and optical limiting are discussed.


Self‐Refraction Of Nonlinear Capillary‐Gravity Waves, Partha P. Banerjee, Adrianus Korpel, Karl E. Lonngren 2016 University of Dayton

Self‐Refraction Of Nonlinear Capillary‐Gravity Waves, Partha P. Banerjee, Adrianus Korpel, Karl E. Lonngren

Partha Banerjee

Self‐refraction effects have been observed during the propagation of deep‐water capillary‐gravity waves. The observations are shown to be in qualitative agreement with the theory of self‐focusing and defocusing in a cubically nonlinear medium in the presence of diffraction.


Single-Beam Holographic Tomography Creates Images In Three Dimensions, George Nehmetallah, Partha P. Banerjee, Nickolai Kukhtarev 2016 The Catholic University of America

Single-Beam Holographic Tomography Creates Images In Three Dimensions, George Nehmetallah, Partha P. Banerjee, Nickolai Kukhtarev

Partha Banerjee

In digital holography (DH), the interference between light scattered from an object and a reference wave is recorded using a CCD camera. DH has various advantages over analog holography: no film processing is needed, reconstruction is performed using numerical methods, and no further experimental setup is necessary. However, one of the disadvantages of DH is that current CCDs have a resolution of approximately 1,000 lines/mm, which is less than that of photographic film.


Digital Commons powered by bepress