Dispersive optical solitons by semi-inverse variational principleSiercke Beatrice and Dr. Anjan Biswas

Center for Research and Education in Optical Sciences and Applications (CREOSA)Mathematics Department University f California Los Angeles, Los Angeles, CADepartment of Mathematical Sciences, Delaware State University, Dover, DE

AbstractIn this work, the dispersive optical solitons is studied by the aid of He’s semi-inverse variational principle. The inter-modal dispersion as well as higher order dispersion terms are taken into account. These include the third order and fourth order dispersion terms. There are three types of nonlinearity that are studied here. They are Kerr-law, power-law and the log-law. In each of these cases, a closed form analytical solution is obtained for the dispersive optical soliton. The domain restrictions and constraints are also identified during the process of obtaining the solution.

Detection of Water in Soil with LIBSChristopher Collins, Alissa Mezzacappa, and Dr. Noureddine Melikechi

Center for Applied Optics for Space Sciences (CAOSS)Department of Physics and Pre-Engineering, Delaware State University, Dover, DE

AbstractLaser induced based spectroscopy (LIBS) is a process of focusing high powered laser onto plasma then watching the plasma excite. With the excitement we can define elements based on the emission spectrum recorded from the plasma the LIBS process creates. The LIBS process can be used in space exploration applications such as gathering surface samples to learn what is contained in them. The LIBS process can be applied to a wide range of experiments as a means of elemental analysis. This technology can be used on board of NASA rovers and Landers to conduct analysis of surface samples giving swift response from a non-destructive, portable system. With Martian and Lunar soil we will use these samples in the LIBS process and determine the necessary water to bind the sample and maintain at the lowest pressures at 7 Torr, similar to Martian atmospheric conditions. After this detection we will identify elements and analyze quantitatively. We will use a Vacuum containing a chamber where the LIBS process will take place and a Turbo pump will be attached to create the lower Martian like pressure. After that the spectra will be obtained and we will analyze results.

Measurement of Resonant Magneto-Optical Rotation in Rubidium Vapor for Atomic MagnetometryBryan Greenly and Dr. Gour S. Pati

Center for Applied Optics for Space Sciences (CAOSS)Department of Physics and Pre-Engineering, Delaware State University,

Dover, DE 199901Abstract

This study reports measurement of resonant magneto-optical rotation (MOR) in rubidium vapor near D1 transition at 795 nm. This effect can be used to design a highly sensitive atomic magnetometer, which can be applied in measuring nuclear magnetism, magnetic resonance imaging and geophysical field measurements etc. In addition to experimental results, our study presents results using a semi-classical theoretical model that provides a simple description of the light-matter interaction in the atomic vapor, and the resonant MOR effect.

Analysis of Dynamic Light Scattering of Concentrated Ficoll SolutionsDanielle Ferguson (summer student), Hacene Boukari (Instructor)

Abstract

Dynamic light scattering (DLS) is a high-resolution optical technique, commonly applied to assess the sizes of nanoparticles in solutions as well as the structure of polymeric systems. In this research project we analyze DLS data collected from five different concentrations (7, 20, 100, 150, 300, and 500 mg/ml) of Ficoll at different scattering angles. The reason we chose Ficoll because it is a neutral, branched polymer readily dissolved in an aqueous solution at higher concentrations. We are developing mathematical fitting routines to extract relevant physical parameters from the DLS data such as the size of ficoll or relaxation times of concentrated solutions. At low concentration ( 7 mg/ml) we determined the size of the ficoll nanoparticle to be about 11 nm. At 20 mg/ml concentration, the data indicate interactions between the ficoll nanoparticles. At higher concentrations, we are using a two component of stretched exponential (Aexp{(-t/a)a} + Bexp{(-t/b)b}) of the electric field to determine the fitting parameters a and b, and a and b, the latter being related to the relaxation times of the solutions.

Stable FDTD simulations of electromagnetic cloaking structuresDorian Foster and Dr. Jinjie Liu

Center for Research and Education in Optical Sciences and Applications (CREOSA)Department of Mathematical Sciences, Delaware State University, Dover, DE

AbstractIn recent years, there has been tremendous interest in electromagnetic invisibility cloaking devices. Methods based on coordinate transformation for designing electromagnetic cloaking structures have been reported. The FDTD method (Yee’s scheme) is a popular and very successful method for solving Maxwell’s equations and it has a wide range of applications in computational electromagnetism. In this study, we have applied the Finite-Difference Time-Domain (FDTD) method to simulate electromagnetic wave propagation near the cloaking devices. Our numerical solution shows that the conventional FDTD method causes large errors due to the material anisotropy inside the cloaking shell. In order to overcome this problem, we have applied the anisotropic FDTD approach to minimize the error. Numerical simulations show that the anisotropic FDTD gives much better result than the conventional FDTD method.

Laser Induced Breakdown Spectroscopy for Micro-Particle Assay Development

Miranda Spina, Dr. Yuri Markushin and Dr. Noureddine MelikechiCenter for Applied Optics for Space Sciences (CAOSS)

Department of Physics and Pre-Engineering, Delaware State University, Dover, DE 199901

AbstractParticle based assays are among most reliable, robust and fastest methods for biomarker diagnostics due to their big active surface-to-volume ratio. We report on the use of the fluorescent dyes and iron oxide micro-particles for the Laser Induced Breakdown Spectroscopy (LIBS) based assay development. Amplitudes of the chosen Iron emission lines have been plotted against particle load to obtain LIBS calibration curves and to estimate the Limit of Detection. Additionally, the obtained spectroscopic data were analyzed by Principal Component Analysis method to determine better Limit of Detection. Comparison between two approaches will help to establish a more sensitive analytical method for the future micro-particle assay development.

Database for spectroscopic dataJessica McDaniel, Samantha McDaniel, Dr. Dragoljub Pokrajac

Center for Research and Education in Optical Sciences and Applications (CREOSA) Department of Information Science, University of Pittsburgh, Pittsburgh, PA

Department of Computer and Information Sciences, Delaware State University

AbstractDuring the process of acquisition and analysis of spectroscopic data, there is need to keep track of metadata (information about the experimental settings, the experimenter, etc) as well as of the data-postprocessing applied to generate various data products. We propose a web-accessible database of spectroscopic data that can answer to needs to experimenters and data analysts. The goal is to provide capability of tracking data sources (type of experiment, e.g., LIBS, FTIR), handle different data formats (.opj, .txt, .xlsx, .mat) and improve quality of generated analytic results.

Wavefront Distortions of a Beam of Light Due to Thermal LensingWhitlee Haymore and Aristides Marcano

Center for Research and Education in Optical Sciences and Applications (CREOSA)Department of Biology, Grambling State University, Grambling, LA 71245

Department of Physics and Pre-Engineering, Delaware State University, Dover, DEAbstract

We report on the measurement of wavefront distortions of a beam of light that propagates in an absorbing media due to thermal lensing effect. We evaluate the wave-front distortion for single beam and pump-probe photothermal lens experimental configurations. Images of the beams are registered as function of the sample position. We compare different ways of processing the images in order to optimize the sample response.

Grain size effect in Laser Induced Breakdown SpectroscopyTariq Sanda, Antoine McLean, Dr. Poopalasingam Sivakumar, and Dr. Noureddine Melikechi Center for Research and Education in Optical Sciences and Applications (CREOSA) Center for Applied Optics for Space Sciences (CAOSS)Mathematics and Physics, Vassar College, Poughkeepsie, NY 12604Nuclear Engineering, South Carolina State University, Orangeburg, SC 29117Department of Physics and Pre-Engineering, Delaware State University, Dover, DE 199901

Abstract

The grain size effects in carbon and iron mixtures were examined on the measured intensities of Laser Induced Breakdown Spectroscopy (LIBS) emission lines. The plasma radiation formed at the sample surface by a Q-switched Nd:YAG laser operating at 1064-nm was detected by using an Echelle Spectrometer. Pressed powder pellet samples of carbon and iron mixture with 50:50 ratios were ablated in atmosphere. For this study, the particulate sizes of Iron and Carbon were changed in association with the laser spot size, where two different particle sizes of Iron (<10µm and <45µm) and four different lenses (45mm, 50mm,60mm, and 75mm focal lengths) were used.