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Full-Text Articles in Nanoscience and Nanotechnology

Exploration Of Efficient Scintillation Based On Inas Quantum Dots In A Gaas Matrix, Katherine Rose Dropiewski Jan 2020

Exploration Of Efficient Scintillation Based On Inas Quantum Dots In A Gaas Matrix, Katherine Rose Dropiewski

Legacy Theses & Dissertations (2009 - 2024)

Scintillation and optical properties of an integrated InAs/GaAs Quantum Dot (QD) Scintillation Detector were investigated to improve efficiency and reduce the decay time of luminescence. The photoluminescent properties of InAs QDs embedded in a GaAs matrix were studied as-grown by molecular beam epitaxy (MBE) on GaAs substrates, and on foreign substrates fabricated as thick (10-25 μm) waveguides. The luminescent efficiency of QDs as-grown on GaAs substrates were examined using photoluminescence (PL) measurements at room temperature and the thermal quenching of PL was analyzed by comparing the integrated PL intensities at 77K-400K. PL measurements were used to optimize QD AlAs capping, …


Degradation And Exciton Energy Transfer Studies In Single-Walled Carbon Nanotube Bundles, Abhishek Gottipati Jan 2016

Degradation And Exciton Energy Transfer Studies In Single-Walled Carbon Nanotube Bundles, Abhishek Gottipati

Legacy Theses & Dissertations (2009 - 2024)

Single walled carbon nanotubes (SWNTs) due to their unique optical behavior, large surface area, robust mechanical strength and electrical properties make them one of the ideal candidates for sensing and opto-electronic applications. In this work, we explore the energy transfer (exciton energy transfer-EET) phenomena occurring between nanotubes in bundles, using resonance Raman spectroscopy.


Ion Beam Nano-Engineering Of Erbium Doped Silicon For Enhanced Light Emission At 1.54 Microns, Sebastian Naczas Jan 2013

Ion Beam Nano-Engineering Of Erbium Doped Silicon For Enhanced Light Emission At 1.54 Microns, Sebastian Naczas

Legacy Theses & Dissertations (2009 - 2024)

Erbium doped silicon is of great interest as a potential light source in Silicon Photonics research due to its light emission at 1.54 μm, which corresponds to the minimal loss of optical transmission in silica fibers for telecommunications. In this thesis a basic mechanism for excitation and de-excitation of Er in Si is reviewed. Based on such fundamental understanding, an innovative approach is proposed and implemented to improve Er luminescence properties through the formation of metal nanoparticles via impurity gettering in Si nanocavities.


Materials Engineering For Near-Infrared Light Emission From Silicon Compatible Mos Structures, Himani Suhag Kamineni Jan 2012

Materials Engineering For Near-Infrared Light Emission From Silicon Compatible Mos Structures, Himani Suhag Kamineni

Legacy Theses & Dissertations (2009 - 2024)

Silicon-based photonics requires several components, such as a light source, an amplifier/waveguide to transfer the signal, and a photodetector to detect the signal. The motivation for using these silicon-based technologies in photonics applications is two-fold: economic advantages offered by the compatibility with mature silicon IC manufacturing and its excellent material properties for photonic devices (high thermal conductivity, high optical damage threshold, etc.). One of the major challenges in the realization of this technology is the Si-based light source. Because of its indirect bandgap, silicon has very inefficient band-to-band radiative electron-hole recombination. To overcome this obstacle, tremendous research efforts have been …


Electron-Phonon Interactions And Quantum Confinement Effects On Optical Transitions In Nanoscale Silicon Films, Vimal Kumar Kamineni Jan 2011

Electron-Phonon Interactions And Quantum Confinement Effects On Optical Transitions In Nanoscale Silicon Films, Vimal Kumar Kamineni

Legacy Theses & Dissertations (2009 - 2024)

Theoretical studies have attributed the temperature dependence of the linear optical response (dielectric function) of bulk semiconductors to electron-phonon interactions and thermal expansion of the lattice. However, the role of phonons in the optical properties of nanoscale structures is often overlooked. This thesis systematically investigates the impact of both carrier confinement and electron-phonon interactions using nanoscale films of silicon in crystalline silicon quantum wells (c-Si QW). Spectroscopic ellipsometry (SE) is a linear optical technique used to of extract the dielectric function and thickness of very thin films. X-ray reflectivity (XRR) was used as the complementary thickness metrology method. The dielectric …