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Articles 1 - 30 of 114

Full-Text Articles in Nanoscience and Nanotechnology

Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure, Desalegn Tadesse Debu May 2019

Plasmonic Properties Of Nanoparticle And Two Dimensional Material Integrated Structure, Desalegn Tadesse Debu

Theses and Dissertations

Recently, various groups have demonstrated nano-scale engineering of nanostructures for optical to infrared wavelength plasmonic applications. Most fabrication technique processes, especially those using noble metals, requires an adhesion layer. Previously proposed theoretical work to support experimental measurement often neglect the effect of the adhesion layers. The first finding of this work focuses on the impact of the adhesion layer on nanoparticle plasmonic properties. Gold nanodisks with a titanium adhesion layer are investigated by calculating the scattering, absorption, and extinction cross-section with numerical simulations using a finite difference time domain (FDTD) method. I demonstrate that a gold nanodisk with an adhesive ...


Characterization And Optimization Of Parylene-C Deposition Process Using Scs Parylene Coater, Hannah Hastings, Eric D. Johnston, Gyuseok Kim Jan 2019

Characterization And Optimization Of Parylene-C Deposition Process Using Scs Parylene Coater, Hannah Hastings, Eric D. Johnston, Gyuseok Kim

Tool Data

Parylene-C has been deposited on bare Si wafers by physical vapor deposition using the SCS Coating Systems. Results show a 12 µm thick Parylene-C film with 10 g of dimer and negligible thickness variation across a wafer. We find a positive linear relationship between film thickness and mass of dimer at a range of 1 g to 18 g. However, the Al boat for dimer was burnt with 18 g of dimer, suggesting multiple depositions with 1 g to 10 g of dimer are recommended to achieve the Parylene-C film thicker than 12 µm.


Photophysical Properties Of Wavelength-Tunable Methylammonium Lead Halide Perovskite Nanocrystals, Daniel J. Freppon, Long Men, Sadie J. Burkhow, Jacob W. Petrich, Javier Vela, Emily A. Smith Jul 2018

Photophysical Properties Of Wavelength-Tunable Methylammonium Lead Halide Perovskite Nanocrystals, Daniel J. Freppon, Long Men, Sadie J. Burkhow, Jacob W. Petrich, Javier Vela, Emily A. Smith

Emily Smith

We present the time-correlated luminescence of isolated nanocrystals of five methylammonium lead mixed-halide perovskite compositions (CH3NH3PbBr3−xIx) that were synthesized with varying iodide and bromide anion loading. All analyzed nanocrystals had a spherical morphology with diameters in the range of 2 to 32 nm. The luminescence maxima of CH3NH3PbBr3−xIx nanocrystals were tuned to wavelengths ranging between 498 and 740 nm by varying the halide loading. Both CH3NH3PbI3 and CH3NH3PbBr3 nanocrystals exhibited no luminescence intermittency for more than 90% of the 250 s analysis time, as defined by a luminescence intensity three standard deviations above the background. The mixed halide ...


Large-Scale Synthesis Of Colloidal Si Nanocrystals And Their Helium Plasma Processing Into Spin-On, Carbon-Free Nanocrystalline Si Films, Pratyasha Mohapatra, Deyny Mendivelso-Perez, Jonathan M. Bobbitt, Santosh Shaw, Bin Yuan, Xinchun Tian, Emily A. Smith, Ludovico Cademartiri Jul 2018

Large-Scale Synthesis Of Colloidal Si Nanocrystals And Their Helium Plasma Processing Into Spin-On, Carbon-Free Nanocrystalline Si Films, Pratyasha Mohapatra, Deyny Mendivelso-Perez, Jonathan M. Bobbitt, Santosh Shaw, Bin Yuan, Xinchun Tian, Emily A. Smith, Ludovico Cademartiri

Emily Smith

This paper describes a simple approach to the large-scale synthesis of colloidal Si nanocrystals and their processing into spin-on carbon-free nanocrystalline Si films. The synthesized silicon nanoparticles are capped with decene, dispersed in hexane, and deposited on silicon substrates. The deposited films are exposed to nonoxidizing room-temperature He plasma to remove the organic ligands without adversely affecting the silicon nanoparticles to form crack-free thin films. We further show that the reactive ion etching rate in these films is 1.87 times faster than that for single-crystalline Si, consistent with a simple geometric argument that accounts for the nanoscale roughness caused ...


Dynamical Thermal Conductivity Of Suspended Graphene Ribbons In The Hydrodynamic Regime, Zlatan Aksamija, Arnab K. Majee Jul 2018

Dynamical Thermal Conductivity Of Suspended Graphene Ribbons In The Hydrodynamic Regime, Zlatan Aksamija, Arnab K. Majee

Zlatan Aksamija

The steady-state behavior of thermal transport in bulk and nanostructured semiconductors has been widely
studied, both theoretically and experimentally. On the other hand, fast transients and frequency dynamics of
thermal conduction has been given less attention. The frequency response of thermal conductivity has become
more crucial in recent years, especially in light of the constant rise in the clock frequencies in microprocessors
and terahertz sensing applications. Thermal conductivity in response to a time-varying temperature field starts
decaying when the frequency exceeds a cutoff frequency Omega_c, which is related to the inverse of phonon relaxation time τ, on the order of ...


Power Dissipation Of Wse2 Field-Effect Transistors Probed By Low- Frequency Raman Thermometry, Zlatan Aksamija, Cameron J. Foss, Arnab K. Majee, Amin Salehi-Khojin Jun 2018

Power Dissipation Of Wse2 Field-Effect Transistors Probed By Low- Frequency Raman Thermometry, Zlatan Aksamija, Cameron J. Foss, Arnab K. Majee, Amin Salehi-Khojin

Zlatan Aksamija

The ongoing shrinkage in the size of two-dimensional (2D) electronic circuitry results in high power densities during device operation, which could cause a significant temperature rise within 2D channels. One challenge in
Raman thermometry of 2D materials is that the commonly used high-frequency modes do not precisely represent the temperature rise in some 2D materials because of peak broadening and intensity weakening at elevated temperatures. In this work, we show that a low-frequency E2g 2 shear mode can be used to accurately extract temperature and measure thermal boundary conductance (TBC) in backgated tungsten diselenide (WSe2) field-effect transistors, whereas the high-frequency ...


Large-Scale Synthesis Of Colloidal Si Nanocrystals And Their Helium Plasma Processing Into Spin-On, Carbon-Free Nanocrystalline Si Films, Pratyasha Mohapatra, Deyny Mendivelso-Perez, Jonathan M. Bobbitt, Santosh Shaw, Bin Yuan, Xinchun Tian, Emily A. Smith, Ludovico Cademartiri May 2018

Large-Scale Synthesis Of Colloidal Si Nanocrystals And Their Helium Plasma Processing Into Spin-On, Carbon-Free Nanocrystalline Si Films, Pratyasha Mohapatra, Deyny Mendivelso-Perez, Jonathan M. Bobbitt, Santosh Shaw, Bin Yuan, Xinchun Tian, Emily A. Smith, Ludovico Cademartiri

Ames Laboratory Accepted Manuscripts

This paper describes a simple approach to the large-scale synthesis of colloidal Si nanocrystals and their processing into spin-on carbon-free nanocrystalline Si films. The synthesized silicon nanoparticles are capped with decene, dispersed in hexane, and deposited on silicon substrates. The deposited films are exposed to nonoxidizing room-temperature He plasma to remove the organic ligands without adversely affecting the silicon nanoparticles to form crack-free thin films. We further show that the reactive ion etching rate in these films is 1.87 times faster than that for single-crystalline Si, consistent with a simple geometric argument that accounts for the nanoscale roughness caused ...


Voltage-Controlled Deposition Of Nanoparticles For Next Generation Electronic Materials, Subhodip Maulik May 2018

Voltage-Controlled Deposition Of Nanoparticles For Next Generation Electronic Materials, Subhodip Maulik

LSU Doctoral Dissertations

This work presents both a feasibility study and an investigation into the voltage-controlled spray deposition of different nanoparticles, namely, carbon nanotubes (CNTs), as well as molybdenum disulfide (MoS2) and tungsten disulfide (WS2) from the transition metal dichalcogenides (TMDCs) family of materials. The study considers five different types of substrates as per their potential application to next-generation device electronics. The substrates selected for this research were: 1) aluminum as a conducting substrate, 2) silicon as a semiconducting substrate, 3) glass, silicon dioxide (SiO2), and syndiotactic poly methyl methacrylate (syndiotactic PMMA) as insulating substrates.

Since the 1990’s, carbon ...


Glucose Level Estimation Based On Invasive Electrochemical, And Non-Invasive Optical Sensing Methods, Sanghamitra Mandal May 2018

Glucose Level Estimation Based On Invasive Electrochemical, And Non-Invasive Optical Sensing Methods, Sanghamitra Mandal

Theses and Dissertations

The purpose of this research is to design and fabricate sensors for glucose detection using inexpensive approaches. My first research approach is the fabrication of an amperometric electrochemical glucose sensor, by exploiting the optical properties of semiconductors and structural properties of nanostructures, to enhance the sensor sensitivity and response time. Enzymatic electrochemical sensors are fabricated using two different mechanisms: (1) the low-temperature hydrothermal synthesis of zinc oxide nanorods, and (2) the rapid metal-assisted chemical etching of silicon (Si) to synthesize Si nanowires. The concept of gold nano-electrode ensembles is then employed to the sensors in order to boost the current ...


Investigation Of Nanomaterial Based Photovoltaic Panel Packaging Materials, Xingeng Yang May 2018

Investigation Of Nanomaterial Based Photovoltaic Panel Packaging Materials, Xingeng Yang

Theses and Dissertations

In this research, nanomaterial-based packaging materials for photovoltaic (PV) panels are investigated. A hydrophobic/anti-reflective surface coating which not only repels water from the top glass of a PV panel but at the same time reduces its light reflectance is investigated. COMSOL simulation results indicate that taller ellipsoid rod (aspect ratio = 5) reflects less light than shorter rod (aspect ratio = 0.5) in the desired spectrum for solar energy harvest from 400nm-700nm. The addition of a polymer layer on these ellipsoid rods broadens the light incident angle from 23° to 34°, from which light can be efficiently absorbed. Based on ...


Design, Fabrication, And Characterization Of All-Inorganic Quantum Dot Light Emitting Diodes, Ramesh Vasan May 2018

Design, Fabrication, And Characterization Of All-Inorganic Quantum Dot Light Emitting Diodes, Ramesh Vasan

Theses and Dissertations

Quantum dot light emitting diodes are investigated as a replacement to the existing organic light emitting diodes that are commonly used for thin film lighting and display applications. In this, all-inorganic quantum dot light emitting diodes with inorganic quantum dot emissive layer and inorganic charge transport layers are designed, fabricated, and characterized. Inorganic materials are more environmentally stable and can handle higher current densities than organic materials. The device consists of CdSe/ZnS alloyed core/shell quantum dots as the emissive layer and metal oxide charge transport layer. The charge transport in these devices is found to occur through resonant ...


Phase Transitions In Monochalcogenide Monolayers, Mehrshad Mehboudi May 2018

Phase Transitions In Monochalcogenide Monolayers, Mehrshad Mehboudi

Theses and Dissertations

Since discovery of graphene in 2004 as a truly one-atom-thick material with extraordinary mechanical and electronic properties, researchers successfully predicted and synthesized many other two-dimensional materials such as transition metal dichalcogenides (TMDCs) and monochalcogenide monolayers (MMs). Graphene has a non-degenerate structural ground state that is key to its stability at room temperature. However, group IV monochalcogenides such as monolayers of SnSe, and GeSe have a fourfold degenerate ground state. This degeneracy in ground state can lead to structural instability, disorder, and phase transition in finite temperature. The energy that is required to overcome from one degenerate ground state to another ...


From Flasks To Applications: Design And Optimization Of Giant Quantum Dots Using Traditional And Automated Synthetic Methods, Christina J. Hanson Apr 2018

From Flasks To Applications: Design And Optimization Of Giant Quantum Dots Using Traditional And Automated Synthetic Methods, Christina J. Hanson

Nanoscience and Microsystems ETDs

Semiconducting nanocrystals, also known as quantum dots (QDs), that emit light with near-unity quantum yield and are extremely photostable are attractive options as down-conversion and direct electricity-to-light materials for a variety of applications including solid-state lighting, display technologies, bio-imaging and optical tracking. Standard QDs with a core/thin shell structure display fluorescence intermittency (blinking) and photobleaching when exposed to prolonged room temperature excitation for single dot measurements, as well as significant reabsorption and energy transfer when densely packed into polymers or at high solution concentrations.

We have developed thick shell “giant” QDs (gQDs), ultra-stable photon sources both at the ensemble ...


Nanostructured Materials Derived From Metal-Organic Frameworks For Energy And Environmental Applications, Zhiqiang Xie Apr 2018

Nanostructured Materials Derived From Metal-Organic Frameworks For Energy And Environmental Applications, Zhiqiang Xie

LSU Doctoral Dissertations

Nowadays, energy and environmental issues have become the top priority among a series of global issues. Fossil fuels as the dominant source are depleted fast and usually lead to some environmental problems. Heavy metal pollution has posed a severe threat to environment and public health. Metal-organic frameworks (MOFs), as a very promising category of porous materials, have attracted more and more interest in research communities due to their extremely high surface areas, diverse nanostructures and unique properties. To meet the ever-increasing energy demand and tackle the heavy metal pollution in water, MOFs can function as ideal templates to prepare various ...


Swelling As A Stabilizing Mechanism During Ion Bombardment Of Thin Films: An Analytical And Numerical Study, Jennifer M. Swenson Apr 2018

Swelling As A Stabilizing Mechanism During Ion Bombardment Of Thin Films: An Analytical And Numerical Study, Jennifer M. Swenson

Mathematics Theses and Dissertations

Irradiation of semiconductor surfaces often leads to the spontaneous formation of rippled structures at certain irradiation angles. However, at high enough energies, these structures are observed to vanish for all angles, despite the absence of any identified, universally-stabilizing physical mechanisms in operation. Here, we examine the effect on pattern formation of radiation-induced swelling, which has been excluded from prior treatments of stress in irradiated films. After developing a suitable continuum model, we perform a linear stability analysis to determine its effect on stability. Under appropriate simplifying assumptions, we find swelling indeed to be stabilizing at wavenumbers typical of experimental observations ...


Phonon Transport At Boundaries And Interfaces In Two-Dimensional Materials, Cameron Foss Jan 2018

Phonon Transport At Boundaries And Interfaces In Two-Dimensional Materials, Cameron Foss

Masters Theses

A typical electronic or photonic device may consist of several materials each one potentially meeting at an interface or terminating with a free-surface boundary. As modern device dimensions reach deeper into the nanoscale regime, interfaces and boundaries become increasingly influential to both electrical and thermal energy transport. While a large majority of the device community focuses on the former, we focus here on the latter issue of thermal transport which is of great importance in implementing nanoscale devices as well as developing solutions for on-chip heat removal and waste heat scavenging. In this document we will discuss how modern performance ...


Parallel Algorithms For Time Dependent Density Functional Theory In Real-Space And Real-Time, James Kestyn Jan 2018

Parallel Algorithms For Time Dependent Density Functional Theory In Real-Space And Real-Time, James Kestyn

Doctoral Dissertations

Density functional theory (DFT) and time dependent density functional theory (TDDFT) have had great success solving for ground state and excited states properties of molecules, solids and nanostructures. However, these problems are particularly hard to scale. Both the size of the discrete system and the number of needed eigenstates increase with the number of electrons. A complete parallel framework for DFT and TDDFT calculations applied to molecules and nanostructures is presented in this dissertation. This includes the development of custom numerical algorithms for eigenvalue problems and linear systems. New functionality in the FEAST eigenvalue solver presents an additional level of ...


Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed Dec 2017

Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed

Electronic Thesis and Dissertation Repository

The fast diminishing of fossil fuels in the near future, as well as the global warming caused by increasing greenhouse gases have motivated the urgent quest to develop advanced materials as cost-effective photoanodes for solar light harvesting and many other photocatalytic applications. Recently, titania nanotube arrays (TNTAs) fabricated by anodization process has attracted great interest due to their excellent properties such as: high surface area, vertically oriented, highly organized, one-dimensional, nanotubular structure, photoactivity, chemical stability and biocompatibility. This unique combination of excellent properties makes TNTAs an excellent photoanode for solar light harvesting. However, the relatively wide band gap energy of ...


Structural And Elastic Properties Of Degenerate Sno Monolayers At Finite Temperature, Afsana Sharmin Dec 2017

Structural And Elastic Properties Of Degenerate Sno Monolayers At Finite Temperature, Afsana Sharmin

Theses and Dissertations

Chalcogen-based layered superconductors with a litharge structure such as FeS and FeSe mono-layers undergo structural and superconducting phase transitions that are tunable by doping. Representing another material platform with a litharge structure but without valence d-electrons, SnO monolayers also display a structural ground state with a degenerate rectangular unit cell at zero temperature and a charge-tunable energy barrier that leads to a thermally-controllable structural phase change. Doped SnO monolayers with rectangular degenerate unit cells give rise to two-dimensional multiferroicity. Their two-dimensional elastic energy landscape adopts a basic analytic expression that is employed to discuss this structural transition. The results contained ...


Generalized Ellipsometry On Complex Nanostructures And Low-Symmetry Materials, Alyssa Mock Dec 2017

Generalized Ellipsometry On Complex Nanostructures And Low-Symmetry Materials, Alyssa Mock

Theses, Dissertations, and Student Research from Electrical & Computer Engineering

In this thesis, complex anisotropic materials are investigated and characterized by generalized ellipsometry. In recent years, anisotropic materials have gained considerable interest for novel applications in electronic and optoelectronic devices, mostly due to unique properties that originate from reduced crystal symmetry. Examples include white solid-state lighting devices which have become ubiquitous just recently, and the emergence of high-power, high-voltage electronic transistors and switches in all-electric vehicles. The incorporation of single crystalline material with low crystal symmetry into novel device structures requires reconsideration of existing optical characterization approaches. Here, the generalized ellipsometry concept is extended to include applications for materials with ...


Optical Absorption Properties Of Ge2–44 And P-Doped Ge Nanoparticles, Wei Qin, Wen-Cai Lu, Li-Zhen Zhao, Kai-Ming Ho, Cai-Zhuang Wang Dec 2017

Optical Absorption Properties Of Ge2–44 And P-Doped Ge Nanoparticles, Wei Qin, Wen-Cai Lu, Li-Zhen Zhao, Kai-Ming Ho, Cai-Zhuang Wang

Ames Laboratory Accepted Manuscripts

The optical absorption properties of non-crystalline and crystalline Ge nanoparticles with the sizes from ∼2.5 to 15 Å have been studied at the B3LYP/6-31G level using time-dependent density functional theory. Hydrogen passivation and phosphorus doping on some selected Ge nanoparticles were also calculated. With the increase of cluster size, the optical absorption spectra of the non-crystalline Ge nanoparticles change from many peaks to a continuous broad band and at the same time exhibit a systematic red-shift. Doping phosphorus also causes the absorption spectra to shift toward the lower energy region for both non-crystalline and crystalline Ge nanoparticles. The ...


Block Copolymer Nanostructures For Inorganic Oxide Nanopatterning, Krishna Pandey Dec 2017

Block Copolymer Nanostructures For Inorganic Oxide Nanopatterning, Krishna Pandey

MSU Graduate Theses

Self-assembled nature of block copolymer (BCP) makes them ideal for emerging technologies in nanometer scale. The micro phase separation between two or more dissimilar polymer blocks of BCP leads to uniform periodic nanostructures of different domains of dimension in the range of 5-100 nm, good for the development of emerging microelectronic and optoelectronics devices. Molecular weight and chain architecture of each blocks govern the morphology evolution; gives different structure like spherical, micelles, lamellae, cylindrical, gyroid etc. The morphology evolution of BCP nanostructure also depends on different external factors as well. In the first work of this thesis, three external factors ...


Nanowire-Based Light-Emitting Diodes: A New Path Towards High-Speed Visible Light Communication, Mohsen Nami Sep 2017

Nanowire-Based Light-Emitting Diodes: A New Path Towards High-Speed Visible Light Communication, Mohsen Nami

Physics & Astronomy ETDs

Nano-scale optoelectronic devices have gained significant attention in recent years. Among these devices are semiconductor nanowires, whose dimeters range from 100 to 200 nm. Semiconductor nanowires can be utilized in many different applications including light-emitting diodes and laser diodes. Higher surface to volume ratio makes nanowire-based structures potential candidates for the next generation of photodetectors, sensors, and solar cells. Core-shell light-emitting diodes based on selective-area growth of gallium nitride (GaN) nanowires provide a wide range of advantages. Among these advantages are access to non-polar m-plane sidewalls, higher active region area compared to conventional planar structures, and reduction of threading ...


Atomistic Simulations Of Novel Nanoscale Semiconductor Devices: Resistance Switches And Two-Dimensional Transistors, Joseph P. Anderson, Mahbubul Islam, David Guzman, Alejandro Strachan Aug 2017

Atomistic Simulations Of Novel Nanoscale Semiconductor Devices: Resistance Switches And Two-Dimensional Transistors, Joseph P. Anderson, Mahbubul Islam, David Guzman, Alejandro Strachan

The Summer Undergraduate Research Fellowship (SURF) Symposium

As transistors get smaller, we are achieving record levels of memory density. However, there is a limit to how small transistors can be made before their functionality breaks down. Thus alternatives to traditional transistor technology are needed. The two such technologies we examined are: resistance switching devices, which reversibly grow metal filaments through a dielectric, and two-dimensional transistors, which are capable of breaking through the scalability limit of traditional transistors. In order to design resistance switching devices which create filaments with some level of consistency, the dynamics of the filament formation need to be explored. Herein we model this process ...


Advanced Purification And Direct-Write 3d Nanoprinting Via Focused Electron Beam Induced Deposition, Brett Bloxton Lewis Aug 2017

Advanced Purification And Direct-Write 3d Nanoprinting Via Focused Electron Beam Induced Deposition, Brett Bloxton Lewis

Doctoral Dissertations

This dissertation addresses three difficulties with focused electron beam induced deposition preventing broader application; purity, spatial control, and mechanical characterization.

Focused electron beam induced deposition (FEBID) has many advantages as a nanoscale fabrication tool. It is compatible for implementation into current lithographic techniques and has the potential to direct-write in a single step nanostructures of a high degree of complexity. FEBID is a very versatile tool capable of fabricating structures of many different compositions ranging from insulating oxides to conducting metals.

Due to the complexity of the technique and the difficulty in directly measuring many important variables, FEBID has remained ...


Interfacial Thermal Transport In Monolayer Mos2- And Graphene-Based Devices, Zlatan Aksamija, Amin Salehi-Khojin, Cameron J. Foss, Arnab K. Majee, Fatemeh Khalili-Araghi Jul 2017

Interfacial Thermal Transport In Monolayer Mos2- And Graphene-Based Devices, Zlatan Aksamija, Amin Salehi-Khojin, Cameron J. Foss, Arnab K. Majee, Fatemeh Khalili-Araghi

Zlatan Aksamija

In many device architectures based on 2D materials, a major part of the heat generated in hot-spots dissipates in the through-plane direction where the interfacial thermal resistances can significantly restrain the heat removal
capability of the device. Despite its importance, there is an enormous (1–2 orders of magnitude) disagreement in the literature on the interfacial thermal transport characteristics of MoS2 and other transition metal dichalcogenides (TMDs) (0.1–14 MW m−2 K−1). In this report, the thermal boundary conductance (TBC) across MoS2 and graphene monolayers with SiO2/Si and sapphire substrates is systematically investigated using a
custom-made ...


Understanding Photovoltaic Properties Of Pbs Quantum Dot Solids Via Solution Contacting, Vitalii Dereviankin, Erik Johansson May 2017

Understanding Photovoltaic Properties Of Pbs Quantum Dot Solids Via Solution Contacting, Vitalii Dereviankin, Erik Johansson

Student Research Symposium

Photovoltaic (PV) devices based on PbS quantum dot (QD) solids demonstrate high photontoelectron conversion yields. However, record power conversion efficiency remain low, in part due to small photovoltages, which in turn are affected by both bulk and interfacial defects. Their relative impacts on limiting the photovoltaic performance of QD solids are not known. Interfacial defects can be formed when contacting a semiconductor and may dominate the semiconductor/metal or metaloxide junction properties. The objective of this study is to explore whether electrochemical contacting using liquid electrolytes provides means of contacting QD solids without introducing interfacial defects. We have initially focused ...


Infrared Energy Conversion In Plasmonic Fields At Two-Dimensional Semiconductors, Gregory Thomas Forcherio May 2017

Infrared Energy Conversion In Plasmonic Fields At Two-Dimensional Semiconductors, Gregory Thomas Forcherio

Theses and Dissertations

Conversion of infrared energy within plasmonic fields at two-dimensional, semiconductive transition metal dichalcogenides (TMD) through plasmonic hot electron transport and nonlinear frequency mixing has important implications in next-generation optoelectronics. Drude-Lorentz theory and approximate discrete dipole (DDA) solutions to Maxwell’s equations guided metal nanoantenna design towards strong infrared localized surface plasmon resonance (LSPR). Excitation and damping dynamics of LSPR in heterostructures of noble metal nanoantennas and molybdenum- or tungsten-disulfide (MoS2; WS2) monolayers were examined by parallel synthesis of (i) DDA electrodynamic simulations and (ii) near-field electron energy loss (EELS) and far-field optical transmission UV-vis spectroscopic measurements. Susceptibility to second-order nonlinear ...


Fabrication And Study Of The Structure And Magnetism Of Rare-Earth Free Nanoclusters, Bhaskar Das Apr 2017

Fabrication And Study Of The Structure And Magnetism Of Rare-Earth Free Nanoclusters, Bhaskar Das

Theses, Dissertations, and Student Research: Department of Physics and Astronomy

No abstract provided.


Single Molecule-Level Study Of Donor-Acceptor Interactions And Nanoscale Environment In Blends, Nicole Quist, Rebecca Grollman, Jeremy Rath, Alex Robertson, Michael Haley, John E. Anthony, Oksana Ostroverkhova Feb 2017

Single Molecule-Level Study Of Donor-Acceptor Interactions And Nanoscale Environment In Blends, Nicole Quist, Rebecca Grollman, Jeremy Rath, Alex Robertson, Michael Haley, John E. Anthony, Oksana Ostroverkhova

Chemistry Faculty Publications

Organic semiconductors have attracted considerable attention due to their applications in low-cost (opto)electronic devices. The most successful organic materials for applications that rely on charge carrier generation, such as solar cells, utilize blends of several types of molecules. In blends, the local environment strongly influences exciton and charge carrier dynamics. However, relationship between nanoscale features and photophysics is difficult to establish due to the lack of necessary spatial resolution. We use functionalized fluorinated pentacene (Pn) molecule as single molecule probes of intermolecular interactions and of the nanoscale environment in blends containing donor and acceptor molecules. Single Pn donor (D ...