Physics Commons^™

Development Of A Panchromatic Acrylamide Based Photopolymer For Multicolour Reflection Holography, Chakrapani Meka, Raghavendra Jallapuram, Izabela Naydenova, Suzanne Martin, Vincent Toal

Articles

The development of a panchromatic acrylamide based photopolymer (ABP) for holographic recording application is presented. The scattering of the recording medium was characterised by measuring the Bidirectional Scattering Distribution Function (BSDF). The dynamic range in reflection mode of recording was evaluated by measuring the diffraction efficiencies of the holographic gratings recorded individually at 633nm, 532nm, and 473nm wavelengths at spatial frequencies of 4200 l/mm, 5000 l/mm and 5700 l/mm respectively. Spectral characterisation of the reflection gratings recorded using a combined single RGB beam was carried out and the reconstructed wavelengths were monitored and compared with the recording wavelengths. The recorded …

Design And Fabrication Of Holographic Optical Elements For Applications In Electronic Speckle Pattern Interferometry And Laser Doppler Vibrometry, Viswanath Bavigadda, Emilia Mihaylova, Raghavendra Jallapuram, Vincent Toal

Conference Papers

An important area of application of holographic optical elements (HOEs) is in optical and electronic speckle pattern interferometry. The design, fabrication and characterization of holographic optical elements (HOEs) for electronic speckle pattern interferometry are presented. Reflection HOEs (RHOEs) were fabricated for use in electronic speckle pattern interferometers (ESPI) and laser Doppler vibrometers (LDV). The HOE-based interferometer is sensitive to out-of-plane displacements only. The results obtained are promising for future applications of the system for modal analysis.

A Systematic Study Of The Dispersion Of Swnts In Organic Solvents, Qiaohuan Cheng, Sourabhi Debnath, Luke O'Neill, Theresa Hedderman, Elizabeth Gregan, Hugh Byrne

Articles

Dispersions of as-produced HiPco single-walled carbon nanotubes (SWNTs) in a series of organic solvents were prepared by dilution with the aid of tip sonication. Mild centrifugation (~ 945 g) was carried out to remove large bundles. Atomic force microscopy (AFM) studies revealed that the bundle size decreased as the dispersion was diluted. By measuring the UV-vis-NIR absorption before and after centrifugation as a function of the concentration, the dispersion limit of SWNTs in each solvent can be determined. Correlations between the dispersion limit and solvent solubility parameters, including the Hildebrand solubility parameter and three dimensional Hansen solubility parameters, are explored, …

Accelerated Lattice Boltzmann Method For Colloidal Suspensions Rheology And Interface Morphology, Hassan Farhat

Wayne State University Dissertations

ABSTRACT

ACCELERATED LATTICE BOLTZMANN MODEL FOR COLLOIDAL SUSPENSIONS RHEOLOGY AND INTERFACE MORPHOLOGY

by

HASSAN FARHAT

July 2010

Advisor: Dr. Singh Trilochan

Co-Advisor: Dr. Joon Sang Lee

Major: Mechanical Engineering

Degree: Doctor of Philosophy

Colloids are ubiquitous in the food, medical, cosmetic, polymer, water purification and pharmaceutical industries. Colloids thermal, mechanical and storage properties are highly dependent on their interface morphology and their rheological behavior.

Numerical methods provide a cheap and reliable virtual laboratory for the study of colloids. However efficiency is a major concern to address when using numerical methods for practical applications.

This work introduces the main building-blocks for …

Innovative Acoustic Reflection Imaging Techniques And Application To Clinical Breast Tomography, Steve Phillip Schmidt

Wayne State University Dissertations

Conventional ultrasound techniques use beam-formed, constant sound speed ray models for fast image reconstruction. However, these techniques are inadequate for the emerging new field of ultrasound tomography (UST). We present a new technique for reconstruction of reflection images from UST data. We have extended the planar Kirchhoff migration method used in geophysics, and combined it with sound speed and attenuation data obtained from the transmission signals to create reflection ultrasound images that are corrected for refractive and attenuative effects.

The resulting techniques were applied to simulated numerical phantom data, physical phantom data and in-vivo breast data obtained with an experimental …

Restructuring Introductory Physics By Adapting An Active Learning Studio Model, Delena Bell Gatch

Physics & Astronomy: Faculty Publications

Despite efforts to engage students in the traditional lecture environment, faculty in Georgia Southern University’s Physics Department became dissatisfied with lecture as the primary means of instruction. During the fall semester of 2006, our department began adapting the studio model to suit the needs of introductory calculus-based physics students at our institution. A studio course seamlessly integrates the lecture and laboratory courses into a single course, devoting much of the class time to active, collaborative, student-centered learning. An emphasis was placed on replacing traditional lectures with interactive, technology enriched class periods designed around the various learning styles. New teaching materials …

Separation Of Transitions With Two Quantum Jumps From Cascades, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

We consider the general scenario of an excited level | i 〉 of a quantum system that can decay via two channels: (i) via a single-quantum jump to an intermediate, resonant level | m 〉, followed by a second single-quantum jump to a final level | f 〉, and (ii) via a two-quantum transition to a final level | f 〉 . Cascade processes | i 〉 → | m 〉 → | f 〉 and two-quantum transitions | i 〉 → | m 〉 → | f 〉 compete (in the latter case, | m 〉 can be both …

Self-Energy Correction To The Hyperfine Splitting And The Electron G Factor In Hydrogenlike Ions, Vladimir A. Yerokhin, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

The hyperfine structure (hfs) and the g factor of a bound electron are caused by external magnetic fields. For the hfs, the magnetic field is due to the nuclear spin. A uniform-in-space and constant-in-time magnetic field is used to probe the bound-electron g factor. The self-energy corrections to these effects are more difficult to evaluate than those to the Lamb shift. Here, we describe a numerical approach for both effects in the notoriously problematic regime of hydrogenlike bound systems with low nuclear charge numbers. The calculation is nonperturbative in the binding Coulomb field. Accurate numerical values for the remainder functions …

Qed Corrections Of Order Α(Zα)²EF To The Hyperfine Splitting Of P1/2 And P3/2 States In Hydrogenlike Ions, Ulrich D. Jentschura, Vladimir A. Yerokhin

Physics Faculty Research & Creative Works

The hyperfine structure (HFS) of a bound electron is modified by the self-interaction of the electron with its own radiation field. This effect is known as the self-energy correction. In this work, we discuss the evaluation of higher order self-energy corrections to the HFS of bound P states. These are expressed in a semianalytic expansion involving powers of Zα and ln(Zα), where Z is the nuclear charge number and α is the fine-structure constant. We find that the correction of relative order α (Zα)² involves only a single logarithm ln(Zα) for P_1/2 states [but no term of order …

Self-Energy Correction To The Bound-Electron G Factor Of P States, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

The radiative self-energy correction to the bound-electron g factor of 2P_1/2 and 2P_3/2 states in one-electron ions is evaluated to order α(Zα)². The contribution of high-energy virtual photons is treated by means of an effective Dirac equation, and the result is verified by an approach based on long-wavelength quantum electrodynamics. The contribution of low-energy virtual photons is calculated both in the velocity and in the length gauge, and gauge invariance is verified explicitly. The results compare favorably to recently available numerical data for hydrogenlike systems with low nuclear charge numbers.

Magnetic Excitations In The Spinel Compound Liₓ [Mn₁.₉₆ Li₀.₀₄] O₄ (X=0.2,0.6,0.8,1.0 ): How A Classical System Can Mimic Quantum Critical Scaling, Thomas Heitmann, Alexander Schmets, John Gaddy, Jagat Lamsal, Marcus Petrovic, Thomas Vojta, Wouter Montfrooij

Physics Faculty Research & Creative Works

We present neutron-scattering results on the magnetic excitations in the spinel compounds Li_x [Mn_1.96 Li_0.04] O₄ (x=0.2,0.6,0.8,1.0). We show that the dominant excitations below T~70K are determined by Mn ions located in clusters, and that these excitations mimic the dynamic scaling found in quantum critical systems that also harbor magnetic clusters, such as CeRu_0.5 Fe_1.5 Ge₂. We argue that our results for this classical spinel compound suggest that the unusual response at low temperatures as observed in quantum critical systems that have been driven to criticality through substantial chemical doping is …

Recent Theoretical Progress In Treating Electron Impact Ionization Of Molecules, Ola A. Al-Hagan, Chuangang Ning, Kate L. Nixon, Andrew James Murray, Christopher J. Colyer, Mark A. Stevenson, B. Lohmann, Don H. Madison

Physics Faculty Research & Creative Works

(e,2e) ionization differential cross sections are presented for several molecules. We will compare experimental results with theoretical calculations using the molecular three body distorted wave (M3DW) approximations for H ₂, N₂, H₂O and Formic Acid (FA) using better wave-function for the molecules than we had in previous works. Generally, good agreement is found between the M3DW approach and experiments.

Precision Measurement Of The Hydrogen-Deuterium 1s-2s Isotope Shift, Christian G. Parthey, Arthur Matveev, Janis Alnis, Randolf Pohl, Thomas Udem, Ulrich D. Jentschura, Nikolai Kolachevsky, Theodor W. Hänsch

Physics Faculty Research & Creative Works

Measuring the hydrogen-deuterium isotope shift via two-photon spectroscopy of the 1S-2S transition, we obtain 670994334606(15) Hz. This is a 10-times improvement over the previous best measurement confirming its frequency value. a calculation of the difference of the mean square charge radii of deuterium and hydrogen results in r2d-r2 p=3.82007(65)fm2, a more than twofold improvement compared to the former value.

Four-Body Charge Transfer Processes In Heavy Particle Collisions, Allison L. Harris, Jerry Peacher, Michael Schulz, Don H. Madison

Physics Faculty Research & Creative Works

Fully differential cross sections (FDCS) for proton + helium single capture and transfer-excitation collisions are presented using the Four-Body Transfer-Excitation (4BTE) model. This is a first order perturbative model that allows for any two-particle interaction to be studied. For single capture, the effect of the projectile-nuclear term in the perturbation is examined. It is shown that inclusion of this term results in an unphysical minimum in the FDCS, but is required to correctly predict the magnitude of the experimental results. For transfer-excitation, the role of electron correlation in the target helium atom is studied, and shown to be unimportant in …

A Surface Potential Study Of Ion-Uptake By 5,11,17,23-Tetra-Tert-Butyl-25,27-Diethoxycarbonyl Methyleneoxy-26,28,Dihydroxycalix[4]Arene And 5,17-(3-Nitrobenzylideneamino)-11,23-Di-Tert-Butyl-25,27- Diethoxycarbonyl Methyleneoxy-26,28-Dihydroxycalix[4]Arene Langmuir Blodgett (Lb) Monolayers,, Mary Deasy, James P. Ward, Fintan Kelleher, Vickie Mckee, Faridah L. Supian, Tim H. Richardson

Articles

A study of surface pressure - area (P-A) isotherms, surface potential (ΔV) and effective dipole moment () of two calix[4]arenes, 5,11,17,23-tetra-tert-butyl-25,27-diethoxycarbonyl methyleneoxy-26,28,dihydroxycalix[4]arene (compound I) and 5,17-(3-nitrobenzylideneamino)-11,23-di-tert-butyl-25,27-diethoxycarbonyl methyleneoxy-26,28-dihydroxycalix[4]arene (compound II) LB films which have the same lower rim but different upper rim has been carried out. This work used a NIMA Surface Potential (S-POT) sensor attached to an LB trough. Space filling model or Corey, Pauling and Koltun (CPK) precision molecular models have been used to estimate the size and the flexibility of both calix[4]arenes, which has been confirmed by X-Ray analysis in one case. …

Far-Field Optical Nanoscopy Based On Continuous Wave Laser Stimulated Emission Depletion, C. Kuang, Wei Zhao, Guiren Wang

Faculty Publications

Stimulated emission depletion (STED) microscopy is one of the breakthrough technologies that belong to far-field optical microscopy and can achieve nanoscale spatial resolution. We demonstrate a far-field optical nanoscopy based on continuous wave lasers with different wavelengths, i.e., violet and green lasers for excitation and STED, respectively. Fluorescent dyes Coumarin 102 and Atto 390 are used for validating the depletion efficiency. Fluorescent nanoparticles are selected for characterizing the spatial resolution of the STED system. Linear scanning of the laser beams of the STED system along one line of a microscope slide, which is coated with the nanoparticles, indicates that a …

Measurement Of Charm And Beauty Production In Deep Inelastic Ep Scattering From Decays Into Muons At Hera, S. Chekanov, M. Derrick, S. Magill, B. Musgrave, D. Nicholass, J. Repond, R. Yoshida, Margarita C. K. Mattingly, P. Antonioli, G. Bari, L. Bellagamba, D. Boscherini, A. Bruni, G. Bruni, F. Cindolo, M. Corradi, G. Iacobucci, A. Margotti, R. Nania, A. Polini, S. Antonelli, M. Basile, M. Bindi, L. Cifarelli, A. Contin, S. De Pasquale, G. Sartorelli, A. Zichichi, D. Bartsch, I. Brock, H. Hartmann

Faculty Publications

The production of charm and beauty quarks in ep interactions has been measured with the ZEUS detector at HERA for squared four-momentum exchange Q2>20 GeV2, using an integrated luminosity of 126 pb-1. Charm and beauty quarks were identified through their decays into muons. Differential cross sections were measured for muon transverse momenta pTμ> 1.5 GeV and pseudorapidities -1. 62. 3, as a function of pTμ>, ημ, Q2and Bjorken x. The charm and beauty contributions to the proton structure function F2were also extracted. The results agree with previous measurements based on independent techniques and are well described by QCD …

Measurement Of D+ And ΛC+ Production In Deep Inelastic Scattering At Hera, H. Abramowicz, I. Abt, L. Adamczyk, M. Adamus, R. Aggarwal, S. Antonelli, P. Antonioli, A. Antonov, M. Arneodo, V. Aushev, Y. Aushev, O. Bachynska, A. Bamberger, A. N. Barakbaev, G. Barbagli, G. Bari, F. Barreiro, D. Bartsch, M. Basile, O. Behnke, J. Behr, U. Behrens, L. Bellagamba, A. Bertolin, S. Bhadra, M. Bindi, C. Blohm, T. Bołd, E. G. Boos, M. Borodin, K. Borras, Margarita C. K. Mattingly

Faculty Publications

Charm production in deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 120 pb-1. The hadronic decay channels D+ → KS0π+, Λc+ → pKS0 and Λc+ → Λπ+, and their charge conjugates, were reconstructed. The presence of a neutral strange hadron in the final state reduces the combinatorial background and extends the measured sensitivity into the low transverse momentum region. The kinematic range is 0 < pT (D+,Λc+ ) < 10GeV, |η(D+,Λc+ )| < 1.6, 1.5 < Q2 < 1000GeV2 and 0.02 < y < 0.7. Inclusive and differential cross sections for the production of D+ mesons are compared to next-to-leading-order QCD predictions. The fraction of c quarks hadronising into Λc+ baryons is extracted.

Experimental Studies On The Plasma Bullet Propagation And Its Inhibition, Erdinc Karakas, Mounir Laroussi

Electrical & Computer Engineering Faculty Publications

Plasma bullets generated by atmospheric pressure low temperature plasma jets have recently been an active research topic due to their unique properties and their enhanced plasma chemistry. In this paper, experimental insights into the plasma bullet lifetime and its velocity are reported. Data obtained from intensified charge-coupled device camera and time-resolved optical emission spectroscopy (OES) elucidated the existence of a weakly ionized channel between the plasma bullet and its source (such as the plasma pencil). Factors responsible for the inhibition of the propagation of the bullet, such as low helium mole fraction, the magnitude of the applied voltage, and the …

Design Of Organic Tandem Solar Cells Using Pcpdtbt: Pc61 Bm And P3ht: Pc71bm, Gon Namkoong, Patrick Boland, Keejoo Lee, James Dean

Electrical & Computer Engineering Faculty Publications

We conducted optical and electrical simulations with the goal of determining the optimal design for conjugated polymer-fullerene tandem solar cells using poly[2,6-(4,4-bis-(2-ethylhexyl)- 4H-cyclopenta[2,1- b;3,4- b′] dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT): [6,6]-phenyl C₆₁ butyric acid methyl ester (PC₆₁ BM) as a bottom cell and poly(3-hexylthiophene) (P3HT): [6,6]-phenyl C₇₁ butyric acid methyl ester (PC₇₁BM) as a top cell. The effects of photon density, absorption, balanced and unbalanced charge carrier transport, and bimolecular recombination in the two subcells were incorporated into the simulations. We found that the maximum energy conversion efficiency (η) is 9% when charge carrier mobilities in …