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Properties Of Type-Ii Znte/Znse Submonolayer Quantum Dots Studied Via Excitonic Aharonov-Bohm Effect And Polarized Optical Spectroscopy, Haojie Ji 2016 Graduate Center, City University of New York

Properties Of Type-Ii Znte/Znse Submonolayer Quantum Dots Studied Via Excitonic Aharonov-Bohm Effect And Polarized Optical Spectroscopy, Haojie Ji

All Dissertations, Theses, and Capstone Projects (2014-Present)

In this thesis I develop understanding of the fundamental physical and material properties of type-II ZnTe/ZnSe submonolayer quantum dots (QDs), grown via combination of molecular beam epitaxy (MBE) and migration enhanced epitaxy (MEE). I use magneto-photoluminescence, including excitonic Aharonov-Bohm (AB) effect and polarized optical spectroscopy as the primary tools in this work.

I present previous studies as well as the background of optical and magneto-optical processes in semiconductor nanostructures and introduce the experimental methods in Chapters 1 - 3.

In Chapter 4 I focus on the excitonic AB effect in the type-II QDs. I develop a lateral tightly-bound exciton model ...


Novel Electrolytes For Use In New And Improved Batteries: An Nmr Study, Marc B. Berman 2016 Graduate Center, City University of New York

Novel Electrolytes For Use In New And Improved Batteries: An Nmr Study, Marc B. Berman

All Dissertations, Theses, and Capstone Projects (2014-Present)

This thesis focuses on the use of nuclear magnetic resonance (NMR) spectroscopy in order to study materials for use as electrolytes in batteries. The details of four projects are described in this thesis as well as a brief theoretical background of NMR. Structural and dynamics properties were determined using several NMR techniques such as static, MAS, PFG diffusion, and relaxation to understand microscopic and macroscopic properties of the materials described within. Nuclei investigate were 1H, 2H, 7Li, 13C, 19F, 23Na, and 27Al. The first project focuses on an exciting new material to be used as a solid electrolyte membrane. T ...


Zncdmgse As A Materials Platform For Advanced Photonic Devices: Broadband Quantum Cascade Detectors And Green Semiconductor Disk Lasers, Joel De Jesus 2016 Graduate Center, City University of New York

Zncdmgse As A Materials Platform For Advanced Photonic Devices: Broadband Quantum Cascade Detectors And Green Semiconductor Disk Lasers, Joel De Jesus

All Dissertations, Theses, and Capstone Projects (2014-Present)

The ZnCdMgSe family of II-VI materials has unique and promising characteristics that may be useful in practical applications. For example they can be grown lattice matched to InP substrates with lattice matched bandgaps that span from 2.1 to 3.5 eV, they can be successfully doped n-type, have a large conduction band offset (CBO) with no intervalley scattering present when strained, they have lower average phonon energies, and the InP lattice constant lies in the middle of the ZnSe and CdSe binaries compounds giving room to experiment with tensile and compressive stress. However they have not been studied in ...


Ultrafast Spectroscopy And Energy Transfer In An Organic/Inorganic Composite Of Zinc Oxide And Graphite Oxide, Jeff A. Secor 2016 Graduate Center, City University of New York

Ultrafast Spectroscopy And Energy Transfer In An Organic/Inorganic Composite Of Zinc Oxide And Graphite Oxide, Jeff A. Secor

All Dissertations, Theses, and Capstone Projects (2014-Present)

The energy transfers and nature of defect levels of an organic/inorganic composite of Zinc Oxide and Graphite are studied with multidimensional spectroscopy. The edge and surface states of each composite are uncovered using excitation emission experiments showing which defect states are mediating the energy transfer from the metal oxide to the graphite oxide. Multidimensional time resolved spectroscopy further describes the effect of the carbon phase on the energy transfer pathways in the material.


The Differentialgeometry Package, Ian M. Anderson, Charles G. Torre 2016 Utah State University

The Differentialgeometry Package, Ian M. Anderson, Charles G. Torre

Downloads

This is the entire DifferentialGeometry package, a zip file (DifferentialGeometry.zip) containing (1) a Maple Library file, DifferentialGeometryUSU.mla, (2) a Maple help file DifferentialGeometry.help. This is the latest version of the DifferentialGeometry software; it supersedes what is released with Maple. It has been tested on Maple versions 17, 18, 2015.

Installation instructions


Physical And Electrochemical Area Determination Of Electrodeposited Ni, Co, And Nico Thin Films, Matthew Gira, Kevin Tkacz, Jennifer R. Hampton 2016 Hope College

Physical And Electrochemical Area Determination Of Electrodeposited Ni, Co, And Nico Thin Films, Matthew Gira, Kevin Tkacz, Jennifer R. Hampton

Faculty Publications

The surface area of electrodeposited thin films of Ni, Co, and NiCo was evaluated using electrochemical double-layer capacitance, electrochemical area measurements using the [Ru(NH3)6]3+/[Ru(NH3)6]2+ redox couple, and topographic atomic force microscopy (AFM) imaging. These three methods were compared to each other for each composition separately and for the entire set of samples regardless of composition. Double-layer capacitance measurements were found to be positively correlated to the roughness factors determined by AFM topography. Electrochemical area measurements were found to be less correlated with measured roughness factors as well as applicable only to ...


Sign Learning Kink-Based (Silk) Quantum Monte Carlo For Molecular Systems, Xiaoyao Ma, Randall W. Hall, Frank Löffler, Karol Kowalski, Kiran Bhaskaran-Nair, Mark Jarrell, Juana Moreno 2016 Department of Physics and Astronomy, Louisiana State University, Baton Rouge

Sign Learning Kink-Based (Silk) Quantum Monte Carlo For Molecular Systems, Xiaoyao Ma, Randall W. Hall, Frank Löffler, Karol Kowalski, Kiran Bhaskaran-Nair, Mark Jarrell, Juana Moreno

Collected Faculty Scholarship

The Sign Learning Kink (SiLK) based Quantum Monte Carlo (QMC) method is used to calculate the ab initioground state energies for multiple geometries of the H2O, N2, and F2 molecules. The method is based on Feynman’s path integral formulation of quantum mechanics and has two stages. The first stage is called the learning stage and reduces the well-known QMC minus sign problem by optimizing the linear combinations of Slater determinants which are used in the second stage, a conventional QMC simulation. The method is tested using different vector spaces and compared to the results of ...


Quantum Violation Of The Pigeonhole Principle And The Nature Of Quantum Correlations, Yakir Aharonov, Fabrizio Colombo, S. Popescu, Irene Sabadini, Daniele C. Struppa, Jeff Tollaksen 2016 Chapman University

Quantum Violation Of The Pigeonhole Principle And The Nature Of Quantum Correlations, Yakir Aharonov, Fabrizio Colombo, S. Popescu, Irene Sabadini, Daniele C. Struppa, Jeff Tollaksen

Mathematics, Physics, and Computer Science Faculty Articles and Research

The pigeonhole principle: "If you put three pigeons in two pigeonholes at least two of the pigeons end up in the same hole" is an obvious yet fundamental principle of Nature as it captures the very essence of counting. Here however we show that in quantum mechanics this is not true! We find instances when three quantum particles are put in two boxes, yet no two particles are in the same box. Furthermore, we show that the above "quantum pigeonhole principle" is only one of a host of related quantum effects, and points to a very interesting structure of quantum ...


Light Propagation And Interaction Observed With Electrons, Robert Campbell Word, Joseph P. S. Fitzgerald, Rolf Kӧnenkamp 2015 Portland State University

Light Propagation And Interaction Observed With Electrons, Robert Campbell Word, Joseph P. S. Fitzgerald, Rolf Kӧnenkamp

Rolf Könenkamp

We discuss possibilities for a microscopic optical characterization of thin films and surfaces based on photoemission electron microscopy. We show that propagating light with wavelengths across the visible range can readily be visualized, and linear and non-linear materials properties can be evaluated non-invasively with nanometer spatial resolution. While femtosecond temporal resolution can be achieved in pump-probe-type experiments, the interferometric approach presented here has typical image frame times of ~200 fs.


Theoretical Estimates Of Spherical And Chromatic Aberration In Photoemission Electron Microscopy, Joseph P.S. Fitzgerald, Rolf Kӧnenkamp, Robert Campbell Word 2015 Portland State University

Theoretical Estimates Of Spherical And Chromatic Aberration In Photoemission Electron Microscopy, Joseph P.S. Fitzgerald, Rolf Kӧnenkamp, Robert Campbell Word

Rolf Könenkamp

We present theoretical estimates of the mean coefficients of spherical and chromatic aberration for low energy photoemission electron microscopy (PEEM). Using simple analytic models, we find that the aberration coefficients depend primarily on the difference between the photon energy and the photoemission threshold, as expected. However, the shape of the photoelectron spectral distribution impacts the coefficients by up to 30%. These estimates should allow more precise correction of aberration in PEEM in experimental situations where the aberration coefficients and precise electron energy distribution cannot be readily measured.


Utilitarian Moral Judgments Are Cognitevely Too Demanding, Sergio Da Silva, Raul Matsushita, Maicon De Sousa 2015 Federal University of Santa Catarina

Utilitarian Moral Judgments Are Cognitevely Too Demanding, Sergio Da Silva, Raul Matsushita, Maicon De Sousa

Sergio Da Silva

We evaluate utilitarian judgments under the dual-system approach of the mind. In the study, participants respond to a cognitive reflection test and five (sacrificial and greater good) dilemmas that pit utilitarian and non-utilitarian options against each other. There is judgment reversal across the dilemmas, a result that casts doubt in considering utilitarianism as a stable, ethical standard to evaluate the quality of moral judgments. In all the dilemmas, participants find the utilitarian judgment too demanding in terms of cognitive currency because it requires non-automatic, deliberative thinking. In turn, their moral intuitions related to the automatic mind are frame dependent, and ...


Coupling Of Isotropic And Directional Interactions And Its Effect On Phase Separation And Self-Assembly, Debra Audus, Francis Starr, Jack Douglas 2015 Wesleyan University

Coupling Of Isotropic And Directional Interactions And Its Effect On Phase Separation And Self-Assembly, Debra Audus, Francis Starr, Jack Douglas

Francis Starr

The interactions of molecules and particles in solution often involve an interplay between isotropic and highly directional interactions that lead to a mutual coupling of phase separation and selfassembly. This situation arises, for example, in proteins interacting through hydrophobic and charged patch regions on their surface and in nanoparticles with grafted polymer chains, such as DNA. As a minimal model of complex fluids exhibiting this interaction coupling, we investigate spherical particles having an isotropic interaction and a constellation of five attractive patches on the particle’s surface. Monte Carlo simulations and mean-field calculations of the phase boundaries of this model ...


Diamond Family Of Nanoparticle Superlattices, Wenyan Liu, Miho Tagawa, Huolin Xin, Tong Wang, Hamed Emamy, Huilin Li, Kevin Yager, Alexei Tkachenko, Francis Starr, Oleg Gang 2015 Wesleyan University

Diamond Family Of Nanoparticle Superlattices, Wenyan Liu, Miho Tagawa, Huolin Xin, Tong Wang, Hamed Emamy, Huilin Li, Kevin Yager, Alexei Tkachenko, Francis Starr, Oleg Gang

Francis Starr

Diamond lattices formed by atomic or colloidal elements exhibit remarkable functional properties. However, building such structures via self-assembly has proven to be challenging because of the low packing fraction, sensitivity to bond orientation, and local heterogeneity. We report a strategy for creating a diamond superlattice of nano-objects via self-assembly and demonstrate its experimental realization by assembling two variant diamond lattices, one with and one without atomic analogs. Our approach relies on the association between anisotropic particles with well-defined tetravalent binding topology and isotropic particles. The constrained packing of triangular binding footprints of truncated tetrahedra on a sphere defines a unique ...


Understanding And Reducing The Anthropogenic Heat Emission, Nektarios Chrysoulakis, C.S.B. Grimmond 2015 Foundation for Research and Technology - Hellas (FORTH)

Understanding And Reducing The Anthropogenic Heat Emission, Nektarios Chrysoulakis, C.S.B. Grimmond

N. Chrysoulakis

Anthropogenic heat emission includes heat generated by the combustion process in vehicles, heat emitted by industrial processes, the conduction of heat through building walls, or emitted directly into the atmosphere by air-conditioning systems and the metabolic heat produced by humans. The magnitude of the anthropogenic heat flux is highly dependent on the spatial scale at which it is estimated. In cities, peak values are associated with large buildings and busy roads. In terms of its temporal variability, the diurnal profile of total anthropogenic heating has local peaks in the early-morning and late-afternoon, corresponding to peaks in transportation and building energy ...


Estimating Urban Pm10 And Pm2.5 Concentrations, Based On Synergistic Meris/Aatsr Aerosol Observations, Land Cover And Morphology Data, A. Beloconi, Y. Kamarianakis, Nektarios Chrysoulakis 2015 Foundation for Research and Technology - Hellas (FORTH)

Estimating Urban Pm10 And Pm2.5 Concentrations, Based On Synergistic Meris/Aatsr Aerosol Observations, Land Cover And Morphology Data, A. Beloconi, Y. Kamarianakis, Nektarios Chrysoulakis

N. Chrysoulakis

This study evaluates alternative spatio-temporal approaches for quantitative estimation of daily mean Particulate Matter (PM) concentrations. Both fine (PM2.5) and coarse (PM10) concentrations were estimated over the area of London (UK) for the 2002–2012 time period, using Aerosol Optical Thickness (AOT) derived from MERIS (Medium Resolution Imaging Spectrometer)/AATSR (Advanced Along-Track Scanning Radiometer) synergistic observations at 1 km × 1 km resolution. Relative humidity, temperature and the K-Index obtained from MODIS (Moderate Resolution Imaging Spectroradiometer) sensor were used as additional predictors. High-resolution (100 m × 100 m) local urban land cover and morphology datasets were incorporated in the ...


A Method For Achieving Analytic Formulas For Three Body Integrals Consisting Of Powers And Exponentials In All Three Interparticle Hyllerass Coordinates, Chris M. Keating 2015 Portland State University

A Method For Achieving Analytic Formulas For Three Body Integrals Consisting Of Powers And Exponentials In All Three Interparticle Hyllerass Coordinates, Chris M. Keating

Dissertations and Theses

After an introduction to the variational principle of three body systems via the Helium atom, we present general analytical formulas for the radial parts of integrals that occur when three body systems are described using wave functions that consist of powers and exponentials in all three interparticle Hylleraas coordinates [Hylleraas1929]. This work is an extension of integrals given by Harris, Frolov and Smith, Jr. [Harris2004]. Specifically included are radial integrals encountered in calculations involving the dipole moment matrix element in Hylleraas coordinates that contain a function f(kr1) (such as a spherical Bessel function) in addition to a plane ...


Correlations Of Fault Rock Constitutive Properties Derived From Laboratory Retrieved Data Of The North-Eastern Block Of The Southern San Andreas Fault, Mecca Hills, Ca Via Computational Analysis., Ryan M. Lee 2015 Utah State University

Correlations Of Fault Rock Constitutive Properties Derived From Laboratory Retrieved Data Of The North-Eastern Block Of The Southern San Andreas Fault, Mecca Hills, Ca Via Computational Analysis., Ryan M. Lee

Physics Capstone Project

We aim to characterize fault-structure-related rocks via correlation between the various geophysical characteristics of samples retrieved from the southern San Andreas Fault (SSAF) near the Mecca Hills region in Southern California. Samples from this area were retrieved from the San Andreas Fault Observatory at Depth (SAFOD) near Parkfield, California at a depth of approximately 3km. Core samples of various lithologies were gathered from the borehole and analyzed using various geophysical methods. Emphasis was placed in possible correlations and relationships between varying lithologies and calculated values of unconfined compressional strength (UCS) and cohesion. Using retrieved data from the samples, as well ...


Computation Of A Virtual Tide Corrector To Support Vertical Adjustment Of Autonomous Underwater Vehicle Multibeam Sonar Data, Lawrence H. Haselmaier 2015 University of New Orleans

Computation Of A Virtual Tide Corrector To Support Vertical Adjustment Of Autonomous Underwater Vehicle Multibeam Sonar Data, Lawrence H. Haselmaier

University of New Orleans Theses and Dissertations

One challenge for Autonomous Underwater Vehicle (AUV) multibeam surveying is the limited ability to assess internal vertical agreement rapidly and reliably. Applying an external ellipsoid reference to AUV multibeam data would allow for field comparisons. A method is established to merge ellipsoid height (EH) data collected by a surface vessel in close proximity to the AUV. The method is demonstrated over multiple collection missions in two separate areas. Virtual tide corrector values are derived using EH data collected by a boat and a measured ellipsoid to chart datum separation distance. Those values are compared to measurements by a traditional tide ...


Developing And Testing An Anguilliform Robot Swimming With Theoretically High Hydrodynamic Efficiency, John B. Potts III 2015 University of New Orleans

Developing And Testing An Anguilliform Robot Swimming With Theoretically High Hydrodynamic Efficiency, John B. Potts Iii

University of New Orleans Theses and Dissertations

An anguilliform swimming robot replicating an idealized motion is a complex marine vehicle necessitating both a theoretical and experimental analysis to completely understand its propulsion characteristics. The ideal anguilliform motion within is theorized to produce ``wakeless'' swimming (Vorus, 2011), a reactive swimming technique that produces thrust by accelerations of the added mass in the vicinity of the body. The net circulation for the unsteady motion is theorized to be eliminated.

The robot was designed to replicate the desired, theoretical motion by applying control theory methods. Independent joint control was used due to hardware limitations. The fluid velocity vectors in the ...


Parameterized Spectral Bathymetric Roughness Using The Nonequispaced Fast Fourier Transform, David H. Fabre 2015 University of New Orleans

Parameterized Spectral Bathymetric Roughness Using The Nonequispaced Fast Fourier Transform, David H. Fabre

University of New Orleans Theses and Dissertations

The ocean and acoustic modeling community has specifically asked for roughness from bathymetry. An effort has been undertaken to provide what can be thought of as the high frequency content of bathymetry. By contrast, the low frequency content of bathymetry is the set of contours. The two-dimensional amplitude spectrum calculated with the nonequispaced fast Fourier transform (Kunis, 2006) is exploited as the statistic to provide several parameters of roughness following the method of Fox (1996). When an area is uniformly rough, it is termed isotropically rough. When an area exhibits lineation effects (like in a trough or a ridge line ...


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