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High-Performance Self-Powered Uv Detector Based On Sno2-Tio2 Nanomace Arrays, Duo Chen, Lin Wei, Lingpan Meng, Yanxue Chen, Yufeng Tian, Shishen Yan, Liangmo Mei, Jun Jiao 2018 School of Physics and State Key Laboratory of Crystal MaterialsShandong UniversityJinanPeople’s Republic of China

High-Performance Self-Powered Uv Detector Based On Sno2-Tio2 Nanomace Arrays, Duo Chen, Lin Wei, Lingpan Meng, Yanxue Chen, Yufeng Tian, Shishen Yan, Liangmo Mei, Jun Jiao

Physics Faculty Publications and Presentations

Photoelectrochemical cell-typed self-powered UV detectors have attracted intensive research interest due to their low cost, simple fabrication process, and fast response. In this paper, SnO2-TiO2 nanomace arrays composed of SnO2 nanotube trunk and TiO2 nanobranches were prepared using soft chemical methods, and an environment-friendly self-powered UV photodetector using this nanostructure as the photoanode was assembled. Due to the synergistic effect of greatly accelerated electron-hole separation, enhanced surface area, and reduced charge recombination provided by SnO2-TiO2 nanomace array, the nanostructured detector displays an excellent performance over that based on bare SnO2 arrays. The impact of the growing time of TiO2 branches ...


Author Correction: Femtosecond Laser Mass Spectrometry And High Harmonic Spectroscopy Of Xylene Isomers (Scientific Reports (2018) Doi: 10.1038/S41598-018-22055-9), Abdullah Alharbi, Andrewy E. Boguslavskiy, Dane Austin, Nicolas Thire, D. Wood, P. Hawkins, Felicity McGrath, A. S. Johnson, I. Lopez-Quintas, Bruno Schmidt, Francois Legare, J. P. Marangos, Anh-Thu Le, Ravi Bhardwaj 2018 Missouri University of Science and Technology

Author Correction: Femtosecond Laser Mass Spectrometry And High Harmonic Spectroscopy Of Xylene Isomers (Scientific Reports (2018) Doi: 10.1038/S41598-018-22055-9), Abdullah Alharbi, Andrewy E. Boguslavskiy, Dane Austin, Nicolas Thire, D. Wood, P. Hawkins, Felicity Mcgrath, A. S. Johnson, I. Lopez-Quintas, Bruno Schmidt, Francois Legare, J. P. Marangos, Anh-Thu Le, Ravi Bhardwaj

Physics Faculty Research & Creative Works

The original version of this Article contained a typographical error in the spelling of the author Nicolas Thiré, which was incorrectly given as Nicholas Thiré. Nicolas Thiré was also incorrectly affiliated with 'Instituto de Química Física Rocasolano, IQFR-CSIC, Serrano 119, 28006, Madrid, Spain'. The correct affiliation is listed below.

INRS-EMT, Advanced Laser Light Source, 1650 Lionel-Boulet Bvd, Varennes, J3X1S2, Canada.

This has now been corrected in the PDF and HTML versions of the Article and in the accompanying Supplementary Information file.


Measuring The Practical Particle-In-A-Box: Orthorhombic Perovskite Nanocrystals, Brandon Mitchell, Eric Herrmann, Junhao Lin, Leyre Gomez, Chris de Weerd, Yasufumi Fujiwara, Kazutomo Suenaga, Tom Gregorkiewicz 2018 West Chester University of Pennsylvania

Measuring The Practical Particle-In-A-Box: Orthorhombic Perovskite Nanocrystals, Brandon Mitchell, Eric Herrmann, Junhao Lin, Leyre Gomez, Chris De Weerd, Yasufumi Fujiwara, Kazutomo Suenaga, Tom Gregorkiewicz

Physics

A connection between condensed matter physics and basic quantum mechanics is demonstrated as we use the fundamental 3D particle-in-a-box model to explain the optical properties of semiconductor nanocrystals, which are substantially modified due to quantum confinement. We also discuss recent advances in the imaging and measurement capabilities of transmission electron microscopy, which have made it possible to directly image single nanocrystals while simultaneously measuring their characteristic absorption energies. We introduce the basic theory of nanocrystals and derive a simplified expression to approximate the optical bandgap energy of an orthorhombic nanocrystal. CsPbBr3 perovskite nanocrystals are used to demonstrate this model due ...


Quantum And Classical Transport Of 2d Electrons In The Presence Of Long And Short Range Disorder, Jesse Kanter 2018 The Graduate Center, City University of New York

Quantum And Classical Transport Of 2d Electrons In The Presence Of Long And Short Range Disorder, Jesse Kanter

All Dissertations, Theses, and Capstone Projects

This work focuses on the study of electron transport of 2-D electron gas systems in relation to both fundamental properties of the systems such as disorder and scattering mechanisms, as well as unique magnetoresistance (MR) effects. A large portion of the discussion is built around the use of an in plane magnetic field to vary the ratio between the Zeeman energy between electrons of different spins and the Landau level spacing, creating a tool to control the quantization of the density of states (DOS).

This tool is first used to isolate Quantum Positive Magnetoresistance (QPMR), which grants insight to the ...


Nmr Characterizations Of Candidate Battery Electrolytes, Stephen A. Munoz 2018 The Graduate Center, City University of New York

Nmr Characterizations Of Candidate Battery Electrolytes, Stephen A. Munoz

All Dissertations, Theses, and Capstone Projects

Enormous strides have been made in next-generation power sources to build a more sustainable society. Energy storage has become a limiting factor in our progress, and there are huge environmental and financial incentives to find the next step forward in battery technology. This work discusses NMR methods for characterizing materials for use in battery application, with a special focus on relaxometry and diffusometry. Examples are provided of various recent investigations involving novel candidate electrolyte materials with different collaborators. Works discussed in this thesis include: the characterization of a new disruptive solid polymer electrolyte technology, investigations of the dynamics of super ...


A Student’S Guide To Matlab For Physical Modeling, Philip C. Nelson, Tom Dodson 2018 University of Pennsylvania

A Student’S Guide To Matlab For Physical Modeling, Philip C. Nelson, Tom Dodson

Department of Physics Papers

This tutorial aims to help you teach yourself enough of the Matlab􏱈 programming language to get started on physical modeling, and particularly the problems appearing in Physical Models of Living Systems (Nelson, 2015). This is not an official publication of The MathWorks, Inc. We attempt to maintain it, but no claim is made that every suggestion made here will work properly with future versions of Matlab.

This is a free online document. Code listings that appear in this document, errata, and more can be found online via http://www.physics.upenn.edu/biophys/PMLS/Student ; code can also be accessed ...


Infra-Red Microwave Spectra, Overtones, Degeneracy And Thermal Populations All In One Diagram, Carl W. David 2018 University of Connecticut

Infra-Red Microwave Spectra, Overtones, Degeneracy And Thermal Populations All In One Diagram, Carl W. David

Chemistry Education Materials

An old drawing, which had an error in it, is re-presented (corrected) for understanding the relationships in diatomic vibrational-rotational interactions at the introductory level.


Locality And Nonlocality In The Interaction-Free Measurement, Daniel Rohrlich, Yakir Aharonov, Tomer Landsberger 2018 Ben-Gurion University of the Negev

Locality And Nonlocality In The Interaction-Free Measurement, Daniel Rohrlich, Yakir Aharonov, Tomer Landsberger

Mathematics, Physics, and Computer Science Faculty Articles and Research

We present a paradox involving a particle and a mirror. They exchange a nonlocal quantity, modular angular momentum Lz mod 2ћ, but there seems to be no local interaction between them that allows such an exchange. We demonstrate that the particle and mirror do interact locally via a weak local current 〈Lz mod 2ћ〉w. In this sense, we transform the “interaction-free measurement” of Elitzur and Vaidman, in which two local quantities (the positions of a photon and a bomb in the two arms of a Mach-Zehnder interferometer) interact nonlocally, into a thought experiment in which two nonlocal ...


Stability Of The Interface Between Two Immiscible Liquids During Injection Into A Tapered Hele-Shaw Cell, Zihao Lin, Ivan C. Christov, Daihui Lu 2018 Purdue University

Stability Of The Interface Between Two Immiscible Liquids During Injection Into A Tapered Hele-Shaw Cell, Zihao Lin, Ivan C. Christov, Daihui Lu

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the early twentieth century, petroleum and mining engineers noticed that water does not displace oil uniformly. This phenomenon, when water penetrates through oil, is now known as viscous fingering. This discovery and the following extensive research have contributed to enhancing oil recovery. In this paper, we describe a numerical study conducted on the stability of the interface between two immiscible liquids in converging and diverging Hele-Shaw cells with varying gradients. Hele-Shaw cells are narrow flow geometries that mimic the properties of a porous medium with fixed permeability. By using computational tools built on the OpenFOAM platform, the multiphase flow ...


Steady-State Method To Measure The In-Plane Thermal Conductivity Of Thin Sheet Materials, Evgeny Pakhomenko, Andrew James Wildridge, Abraham Mathew Koshy, Souvik Das, Andreas Jung 2018 Coe College

Steady-State Method To Measure The In-Plane Thermal Conductivity Of Thin Sheet Materials, Evgeny Pakhomenko, Andrew James Wildridge, Abraham Mathew Koshy, Souvik Das, Andreas Jung

The Summer Undergraduate Research Fellowship (SURF) Symposium

A new generation of silicon pixel detectors is required to cope with the unprecedented luminosities at the high-luminosity phase of the Large Hadron Collider (HL-LHC) in 2025. The HL-LHC provides a high radiation, high interaction rate environment for the innermost detector region of the CMS detector. This can lead to an uncontrolled increase in temperature of the detector that can destroy the silicon pixels. Moreover, too high operating temperature can add noise to the data obtained from the detector and can slow the read out cheap down. Therefore, the Phase II upgrade to the Compact Muon Solenoid (CMS) experiment requires ...


Incorporating Collisions And Resistance Into The Transition From Field Emission To The Space Charge Regime, Samuel D. Dynako, Adam M. Darr, Allen L. Garner 2018 Purdue University

Incorporating Collisions And Resistance Into The Transition From Field Emission To The Space Charge Regime, Samuel D. Dynako, Adam M. Darr, Allen L. Garner

The Summer Undergraduate Research Fellowship (SURF) Symposium

Advancements in microelectromechanical systems (MEMS) and microplasmas, particularly with respect to applications in combustion and biotechnology, motivate studies into microscale gas breakdown to enable safe system design and implementation. Breakdown at microscale deviates from that predicted by Paschen’s law due to field emission—the stripping of electrons from the cathode in the presence of strong surface field—and follows the Fowler-Nordheim (FN) law. As injected current increases at this length scale, electrons accumulate in the gap and FN electron emission becomes space charge limited, leading to the Child-Langmuir (CL) law at vacuum and the Mott-Gurney (MG) law at high ...


Majorana Spin-Flip Transition In The Alpha Magnetic Trap, Miguel Alarcon, Colin Riggert, Francis Robicheaux 2018 Universidad de Los Andes - Colombia

Majorana Spin-Flip Transition In The Alpha Magnetic Trap, Miguel Alarcon, Colin Riggert, Francis Robicheaux

The Summer Undergraduate Research Fellowship (SURF) Symposium

The main purpose of the ALPHA collaboration is to trap antihydrogen atoms so that the Charge Conjugation-Parity Transformation-Time Reversal (CPT) symmetry can be tested. The trapping mechanism consists on an octupole magnet that traps the atoms near the magnetic field minima. Once trapped, due to the Majorana spin-flip effect, atoms can escape by changing the orientation of its spin. The magnetic field generated by the octupole magnet present in the trap has multiple zeroes of different orders. These zeroes could affect the probability of a spin flip, and therefore alter the number of escaped atoms. The main problem tackled by ...


Scattering Of Few Photon Fields By Two Level Systems In A One Dimensional Geometry, William Konyk 2018 University of Arkansas, Fayetteville

Scattering Of Few Photon Fields By Two Level Systems In A One Dimensional Geometry, William Konyk

Theses and Dissertations

Recent experimental progress has realized strong, efficient coupling of effective two level systems to waveguides. We study the scattering of multimode photons from such emitters coupled losslessly to the confined geometry of a one dimensional waveguide. We develop novel techniques for describing the scattered state of both single and multi-photon wavepackets and explore how such wavepackets interact with arrays of emitters coupled to a one dimensional waveguide. Finally, we apply these techniques and analyze the capability of two particular systems to act as a quantum conditional logic gate.


Impacts Of Anisotropy, Wave Heating, And Neutral Winds On High-Latitude Ionospheric Dynamics, Meghan R. Burleigh 2018 Embry-Riddle Aeronautical University

Impacts Of Anisotropy, Wave Heating, And Neutral Winds On High-Latitude Ionospheric Dynamics, Meghan R. Burleigh

Dissertations and Theses

Significant amounts of ionospheric plasma can be transported to high altitudes (ion upflow) in response to a variety of plasma heating and uplifting processes such as DC electric fields and precipitation. Once ions have been lifted to high altitudes, transverse ion acceleration by broadband ELF waves can give the upflowing ions sufficient energy for the mirror force to propel these ions to escape into the magnetosphere (ion outflow). In order to accurately examine the connection between upflow and outflow processes, a new two dimensional, anisotropic fluid model is developed.

The new model, named GEMINI-TIA, is based on a Bi-Maxwellian distribution ...


Effect Of Chemistry On Electrodynamics In The Martian Dynamo Region, Morgan M. Matheny 2018 Embry-Riddle Aeronautical University

Effect Of Chemistry On Electrodynamics In The Martian Dynamo Region, Morgan M. Matheny

Dissertations and Theses

Electromagnetic interactions between Mars remnant crustal magnetic fields and solar and planetary ions lead to time and space variations of the ionosphere. In this work, we continue the investigations started by Riousset et al. [2013] and address the effect of chemistry on ion populations in the dynamo region, where ion dynamics are driven by collisions while electrons are still mostly magnetized. We adopt a mesoscale model to simulate dynamics of electrons and ions in the upper atmosphere (100–400 km). Our approach focuses on numerical studies using the Martian Multifluid Magnetohy drodynamic (MF-MHD) Model (M4). The dynamo is a region ...


Investigation Of Stereotactic Body Radiation Therapy Delivery Accuracy On An Elekta Linear Accelerator, Addie Barron 2018 Louisiana State University

Investigation Of Stereotactic Body Radiation Therapy Delivery Accuracy On An Elekta Linear Accelerator, Addie Barron

LSU Master's Theses

Purpose: This work investigated the delivery accuracy of high-dose lung and spine stereotactic treatments delivered with the Elekta Infinity and Versa HD platforms. The accuracy of these platforms will be used for consideration in implementing a spine stereotactic radiosurgery (SSRS) program at Mary Bird Perkins Cancer Center.

Methods: A geometric phantom was used to perform Winston-Lutz type tests that assessed the relevant degrees of freedom (gantry, collimator, and couch) of the delivery system. A lung stereotactic body radiation therapy (SBRT) and spine SRS treatment plan were generated for use in end-to-end testing. Delivery accuracy was tested using a novel diode ...


Activities And Classroom Demonstrations In Biological Physics: A Resource Document, Philip C. Nelson, William Berner 2018 University of Pennsylvania

Activities And Classroom Demonstrations In Biological Physics: A Resource Document, Philip C. Nelson, William Berner

Department of Physics Papers

We give detailed recipes for a number of classroom demonstrations relevant to biological physics instruction. We developed them mainly for use in 2nd-3rd year undergraduate Physics courses. But you can (and we do) use them for primary school, through high school, up to PhD candidates. You adapt the words for each audience, but a phenomenon is a phenomenon.

We also outline a 1-hour introduction to Python for undergraduate scientific computing.

Finally we document some outcomes from courses taught at U Pennsylvania using these resources and others cited here. This material was presented at a workshop at the AAPT meeting in ...


Affine Symmetry, Geodesics, And Homogeneous Spacetimes, David Maughan, Charles G. Torre 2018 Utah State University

Affine Symmetry, Geodesics, And Homogeneous Spacetimes, David Maughan, Charles G. Torre

Charles G. Torre

We show that the conservation laws for the geodesic equation which are associated to affine symmetries can be obtained from symmetries of the Lagrangian for affinely parametrized geodesics according to Noether’s theorem, in contrast to claims found in the literature. In particular, using Aminova’s classification of affine motions of Lorentzian manifolds, we show in detail how affine motions define generalized symmetries of the geodesic Lagrangian. We compute all infinitesimal proper affine symmetries and the corresponding geodesic conservation laws for all homogeneous solutions to the Einstein field equations in four spacetime dimensions with each of the following energy–momentum ...


New Mechanism For Accelerated Removal Of Excess Radiogenic Heat, Russell Humphreys 2018 Creation Research Society

New Mechanism For Accelerated Removal Of Excess Radiogenic Heat, Russell Humphreys

The Proceedings of the International Conference on Creationism

In a technical paper (Humphreys, 2014), I presented Biblical and scientific evidence that (a) space is a physical material that we do not perceive, (b) this fabric of space, and objects within it, are thin in a 4th spatial direction we do not ordinarily perceive, and (c) the fabric is surrounded by a hyperspace of four spatial dimensions. End note 27 of the paper explained that light emitted by objects within the fabric ordinarily would be constrained to travel entirely within the fabric. The end note also proposed that under certain extraordinary conditions the Bible calls the opening of the ...


Modeling Of Flood And Post-Flood Ocean Floor Cooling, William J. Worraker, Richard Ward 2018 Biblical Creation Trust

Modeling Of Flood And Post-Flood Ocean Floor Cooling, William J. Worraker, Richard Ward

The Proceedings of the International Conference on Creationism

Given that the earth’s ocean basins are geologically young, few areas being older than early Jurassic, and that most creation scientists regard Jurassic rocks as Flood deposits, these basins must have formed during and since the Flood, i.e. within no more than 4500 years. This paper represents a first attempt at modeling ocean basin formation by the separation of the continents and cooling of mantle material emplaced at spreading centres well within that limited time. We use a spreadsheet-based finite difference solution of the heat diffusion equation applied to a simple widely-used plate model of ocean lithosphere formation ...


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