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Filtering by: Creator Amsberry, Anthony C. Remove constraint Creator: Amsberry, Anthony C. Advisor Ostroverkhova, Oksana Remove constraint Advisor: Ostroverkhova, Oksana

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  • Optical Tweezer Trapping of Colloidal Polystyrene and Silica Microspheres

    Creator:
    Peters, Kyle C.
    Abstract:
    Optical trapping is a tool used throughout a wide variety of disciplines rang- ing from precisely probing and manipulating sub-micron organisms in biol- ogy to analyzing fundamental charge transfer in colloidal physics. This thesis presents research involving optical tweezer force measurements of polystyrene and silica microspheres. In addition, preliminary work...
    Resource Type:
    Undergraduate Thesis
    Full Text:
    C. Peters An Undergraduate Thesis Submitted to Oregon State University In partial fulfillment for

  • On the photoresponse of several novel oligoacene and anthradithiophene derivatives

    Creator:
    Day, Jonathan
    Abstract:
    The results of an investigation into carrier dynamics in several novel functionalized and solution-processable pentacene and anthradithiophene derivatives are reported. Measurements were made of real-time photoresponse of polycrystalline thin films of these materials to ultrafast laser pulses, on picosecond to microsecond time-scales, as well as measurements of dark current and...
    Resource Type:
    Dissertation
    Full Text:
    thin film between different electrodes. c© Copyright Jonathan Day June 20, 2008 All Rights

  • (Opto)electronic Properties of Xylindein and Organic (Opto)electronic Devices

    Creator:
    Giesbers, Gregory J.
    Abstract:
    Organic semiconductors are of interest for (opto)electronic applications due to their low cost, solution processability, and tunable properties. Natural product-derived organic pigments have attracted attention due to their extraordinary environmental stability and unexpectedly good optoelectronic performance, in spite of only partially conjugated molecular structures. Fungi-derived pigments are a naturally sourced,...
    Resource Type:
    Dissertation
    Full Text:
    -derived pigment xylindein, which is secreted by the wood-staining fungi Chlorociboria (C.) aeruginosa

  • Light-matter interactions : from the photophysics of organic semiconductors to high spatial resolution optical tweezer-controlled nanoprobes

    Creator:
    Kendrick, Mark J.
    Abstract:
    Studies of light-matter interactions in organic semiconductors and in optical tweezer trapping of nanoparticles are presented. In the research related to organic semiconductor materials, a variety of novel materials and their composites have been characterized, and physical mechanisms behind their optoelectronic properties have been established. Three novel functionalized hexacene derivatives...
    Resource Type:
    Dissertation
    Full Text:
    (c)) [16]. The purpose of the side groups is to disrupt the edge-to- face packing in the

  • Electronic and Optical Properties of Organic Semiconductors : Experiment and Simulation

    Creator:
    Johnson, Brian
    Abstract:
    The continued development of organic semiconductor materials relies on an understanding of the relationship between optoelectronic properties, molecular structure, and molecular interaction. Several detailed studies of electronic properties in functionalized polyacene materials are presented. A computational model which allows the extraction of charge generation and transport properties from experimental data...
    Resource Type:
    Dissertation
    Full Text:
    properties and challenges which this source of material present. c©Copyright by Brian Johnson August 4

  • Optoelectronic properties of organic semiconductor materials : from bulk to single molecule

    Creator:
    Shepherd, Whitney E. B.
    Abstract:
    The behavior and application of organic semiconductor materials depend strongly on their molecular structure, and molecular interactions. Several studies of intermolecular interactions in functionalized polyacene materials are presented. The degree and onset of aggregation of a functionalized anthradithiophene derivative was studied as a function of concentration in two different host...
    Resource Type:
    Dissertation
    Full Text:
    nano-environment. c©Copyright by Whitney E. B. Shepherd December 6, 2012 All Rights Reserved

  • Photostability of organic semiconductors : from bulk to nanoscales

    Creator:
    Quist, Nicole Arianne
    Abstract:
    Organic semiconductors have attracted considerable attention due to their applications in low-cost, solution-processable (opto)electronic devices. An important class of high-performance organic semiconductors is pentacene derivatives, which exhibit high charger carrier mobilities in field-effect transistors and ultrafast singlet fission in photovoltaic devices. These derivatives have served as benchmark materials for systematic...
    Resource Type:
    Dissertation
    Full Text:
    . . . . . . . . . . . . . . . 136 C Monte Carlo Simulation Program . . . . . . . . . . . . . . . . . . . . 153 LIST OF FIGURES

  • Photophysics of organic semiconductors at the nanoscale

    Creator:
    Grollman, Rebecca R.
    Abstract:
    Organic semiconductors are used in a wide variety of applications including transistors,solar cells, and light emitting diodes. These materials are solution-processable,low cost, and tunable. Many successful organic optoelectronic materials utilizeblends of several types of molecules (such as donors and acceptors) in order topromote charge generation. As blends are an inherently...
    Resource Type:
    Dissertation
    Full Text:
    while simultaneously measuring surface charge with optical tweezers. c©Copyright by Rebecca R

  • Low temperature microscopy of organic optoelectronic materials

    Creator:
    Thieme, Mattson
    Abstract:
    We present a report on a new capability for low temperature microscopy of organic optoelectronic semiconductor materials. We may now perform photoluminescence (PL) and conductivity measurements as a function of temperature on a microscopic level. Testing confirmed the setup's ability to support microscopic measurements at pressures of 10^-6 Torr and...
    Resource Type:
    Undergraduate Thesis
    Full Text:
    , whose cheerful presence made for an exceptional introduction to scienti�c writing. In addition to Dr

  • Exciton and Polariton Nature in Organic Crystals

    Creator:
    Van Schenck, Jonathan D. B.
    Abstract:
    Understanding the impact of inter-molecular orientation on the optical proper-ties of organic semiconductors is important for designing next-generation organic (opto)electronic and photonic devices. However, fundamental aspects of how various features of molecular packing in crystalline systems determine the nature and dynamics of excitons have been a subject of debate. Toward...
    Resource Type:
    Dissertation
    Full Text:
    thanking his many collaborators: Dr. E. K. Tanyi, Dr. L.-J. Cheng, Dr. J. Anthony, G. Mayonado, Dr. M. W

  • Optical Tweezers-Based Probe of Charge Transfer in Organic Semiconductors at Microscopic Scales

    Creator:
    Busche, Jacob A.
    Abstract:
    A method for measuring the (dis)charging dynamics of organic semiconductors with single-electron resolution in multiple environments is developed using optical tweezers. A 1μm silica bead was coated with either a pristine organic semiconductor or an electron donor-acceptor blend, trapped using optical tweezers, and driven with an oscillating electrical driving force....
    Resource Type:
    Honors College Thesis
    Full Text:
    is larger to denote increased intensity. Rays b and c denote light entering the microsphere from the

  • Exploration of charge-transfer exciton formation in organic semiconductors through transient photoconductivity measurements

    Creator:
    Neunzert, Afina
    Abstract:
    This project investigated transient photoconductivity in organic donor-acceptor (D-A) systems, where a flourinated anthradithiophene, ADT-TES-F, acts as the donor. Various acceptor molecules were used, with different sidegroups, and different HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) energy level offsets relative to the acceptor. Thin film composites...
    Resource Type:
    Undergraduate Thesis
    Full Text:
    structures (shown as R groups in �gure 1). Show here are (a) TIPS, (b) NODIPS, and (c) TCHS

  • Optoelectronic Properties of a Novel Fungi-derived Pigment

    Creator:
    Wiesner, Cameron
    Abstract:
    In industry, there is considerable interest in finding sustainable, renewable materials for use in electronic devices. Pigments derived from spalting fungi are of particular interest due to their longevity in diverse environmental conditions. The focus of my project was to characterizethe properties of a novel, fungi-derived pigment, and to discover...
    Resource Type:
    Undergraduate Thesis
    Full Text:
    .) ganodermophthorum​ is a spalting, or wood-staining, fungus similar to Chlorociboria (C.) aeruginosa​, the spalting

  • Photodimerization of Organic Semiconductors in the Strong Coupling Regime

    Creator:
    Puro, Richard
    Abstract:
    Organic semiconducting materials have emerged in the last few decades as viable alternatives to inorganics in broad applications from field effect transistors to LEDs to solar cells. Organics provide many benefits over inorganics such as flexibility, sustainability, and reduced cost. However, these materials are more susceptible to degradation in the...
    Resource Type:
    Undergraduate Thesis
    Full Text:
    writing of this thesis for the past year, and Dr. John Anthony, from the chemistry department at the

  • Modeling optical reflection and electric field intensity in organic semiconductor microcavities

    Creator:
    Munk, Rebecca
    Abstract:
    Organic semiconductors are a promising alternative to the traditional inorganic semiconductors, such as silicon. Organics are solution-processable, low-cost, sustainable, and have interesting optoelectronic properties. One such property is the formation of exciton-polaritons, quantum quasi-particles formed by an electron-hole pair in the semiconductor and a photon. This process can be induced...
    Resource Type:
    Undergraduate Thesis
    Full Text:
    modes is given as, , 𝑛 𝑒𝑓𝑓 ω 𝑐( )2 − 𝑘||2 = 𝑚π𝐿( )2 (1.4.1) where is the effective index of

  • Study of Organic Semiconductors Using Time-Resolved Charge Measurements at the Microscale

    Creator:
    Wallace, Richard
    Abstract:
    Understanding charge transfer in organic semiconductors is important for developing devices like organic light emitting diodes and flexible electronics. Optical tweezers have been used in many disciplines for trapping, manipulating, and analyzing microscopic objects such as microspheres, micro-organisms, and other colloidal particles. Using optical tweezers, studies have measured the average...
    Resource Type:
    Undergraduate Thesis
    Full Text:
    holder (c). . . . 12 3.2 The experimental setup for the trapping of coated microspheres . . . . . . 13

  • Organic Semiconductors : Incorporating Xylindein into (Opto)Electronic Devices

    Creator:
    Rath, Jeremy J.
    Abstract:
    This research investigates the electronic properties of a fungi-derived pigment, xylindein as a novel sustainable material for organic electronics. Xylindein molecules were characterized in solution and in film. Absorption spectra and (photo)luminescence spectra were taken at various excitation wavelengths. Xylindein’s molecular properties were computed with the Gaussian 09 software suite....
    Resource Type:
    Undergraduate Thesis
    Full Text:
    film made at 250◦±10◦. This shows that xylindein is stable at temperatures of at least 200◦C and that

  • A Study of Charging Behaviors in Organic Semiconductors using Optical Trapping

    Creator:
    Founds, Graham M.
    Abstract:
    We measure the charging and discharging of two organic materials, PCBM and ADT-TES-F. These materials are studied through the noncontact method of particle trapping known as Optical Tweezers, where an IR laser is used to constrain the motion of a coated or noncoated silica sphere while its positional data is...
    Resource Type:
    Undergraduate Thesis
    Full Text:
    histogram. C) The frequency power spectrum of the sphere’s motion. Displays the frequency spectrum of the