Browsing by Author "Bradley, Louise"
Now showing items 21-40 of 130
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Description of polarisation dependence of two-photon absorption in silicon avalanche photodiodes
Donegan, John; Bradley, Louise (2010)A simple formula is obtained that very accurately describes the level of two-photon absorption (TPA) generated by elliptically polarised light in silicon avalanche photodiodes (Si-APDs). The dichroism parameter necessary ... -
Design of microcavity semiconductor devices for highly efficient optical switching and sampling applications
Bradley, Louise; Donegan, John (2002)Summary form only given. Two Photon Absorption (TPA) in semiconductors has recently been shown to be a serious candidate for optical autocorrelation of short pulses, and all-optical switching and sampling of high speed ... -
Direct laser writing of submicron photonic arrays for vapor-responsive sensing
Bradley, Louise (2022)A two photon polymerization technique was used to fabricate 2D photonic crystals based on a vapor-responsive hydrogel. By testing their vapor sensing performance, these photonic arrays were found to exhibit dynamic stimulus ... -
Direct laser writing of vapour-responsive photonic arrays
Florea, Larisa; Bradley, Louise; Delaney, Colm (2021)Using direct laser writing, arrays of optically responsive ionogel structures were fabricated. To demonstrate their responsive nature, visible colour changes in the presence of different solvent vapours were investigated. ... -
Dispersion monitoring for high-speed WDM networks via two-photon absorption in a semiconductor microcavity
Donegan, John; Bradley, Louise (2006)Due to the continued demand for bandwidth, network operators have to increase the data rates at which individual wavelengths operate at. As these data rates will exceed 100 Gbit/s in the next 5-10 years, it will be crucial ... -
Dynamic Pump-probe studies of TE and TM modes in semiconductor optical amplfiers
Bradley, Louise; Philippe, Severine; Landais, Pascal; Martinez-Rosas, Miguel; Surre, Frederick (2005)A contra-propagation set up is implemented and dynamic pump probe studies of a InGaAsP/InP SOA in the gain regime are undertaken using pulses of 2ps duration. The time resolved amplified probe signal is measured separately ... -
Dynamic structural colour using vanadium dioxide thin films
Bradley, Louise (2018)A thin film stack consisting of layers of indium tin oxide (ITO) with an intermediate vanadium oxide (VO2) layer on an optically thick silver film has been investigated for dynamic structural colour. The structure benefits ... -
Dynamical tuning of energy transfer efficiency on a graphene monolayer
Bradley, Louise (2015)In this contribution we present a theoretical investigation of the energy transfer efficiency between quantum systems placed in proximity of a monolayer of conducting graphene. We calculate the spontaneous emission rate ... -
Dynamics of non-linear polarization rotation in semiconductor optical amplifiers
Bradley, Louise (2007)A free space contra-propagation set-up is implemented and a dynamic pump-probe study of a SOA in the picosecond regime is undertaken. The dynamics of the change in the probe state of polarisation is investigated and the ... -
Effect of metal nanoparticle concentration on localized surface plasmon mediated Förster resonant energy transfer
Bradley, Louise; Gounko, Iouri (2012)The influence of gold nanoparticle concentration on signatures of localized surface plasmon mediated Förster resonant energy transfer is investigated in a quantum dot–gold nanoparticle sandwich structure. At lower gold ... -
Electrically Driven Reprogrammable Vanadium Dioxide Metasurface Using Binary Control for Broadband Beam Steering
Bradley, Louise (2022)Resonant optical phased arrays are a promising way to reach fully reconfigurable metasurfaces in the optical and near-infrared (NIR) regimes with low energy consumption, low footprint, and high reliability. Continuously ... -
Electroluminescence of γ-CuBr thin films via vacuum evaporation depositon
Bradley, Louise (2010) -
Emission Properties of Colloidal Quantum Dots on Polyelectrolyte Multilayers
Bradley, Louise; Gounko, Iouri (2006)We present steady state and time-resolved photoluminescence (PL) characteristics of differently charged CdTe quantum dots (QDs) adsorbed onto a polyelectrolyte (PE) multilayer. The PE multilayer is built up using a ... -
Encapsulation of the heteroepitaxial growth of wide band gap γ-CuCl on silicon substrates
Bradley, Louise (2006)γ-CuCl semiconductor material has been identified as a candidate material for the fabrication of blue-UV optoelectronic devices on Si substrates due to its outstanding electronic, lattice and optical properties. However, ... -
Energy transfer in colloidal CdTe quantum dot nanoclusters
Bradley, Louise; Gounko, Iouri (2010)Quantum dot (QD) nanoclusters were formed using oppositely charged colloidal CdTe QDs, of two different sizes, mixed in aqueous solutions. The photoluminescence (PL) spectra and time-resolved PL decays show signatures of ... -
Enhanced Forster resonance energy transfer between CdTe quantum dots in proximity to gold nanoparticles
Bradley, Louise; Komarala, Vamsi K.; Rakovich, Yury P.; Byrne, Stephen J.; Gun'ko, Yurii K.; Rogach, Andrey L. (SPIE, 2007)Förster resonant energy transfer (FRET) between the CdTe quantum dot (QD) acting as donors and acceptors is investigated at nanoscale proximity to gold nanoparticles (Au NPs). Photoluminescence (PL) studies of the acceptor ... -
Enhanced quantum efficiency in mixed donor-acceptor nanocrystal quantum dot monolayers
Gounko, Iouri; Bradley, Louise (2011)Colloidal nanocrystal quantum dots have attracted interest for use in light-harvesting and emitting devices. One of the key parameters for such applications is the quantum efficiency. Nanocrystal quantum dots exhibit reduced ... -
Enhancing Forster nonradiative energy transfer via plasmon interaction
Gounko, Iouri; Bradley, Louise (2016) -
Enhancing the electrical properties of MoS2 through nonradiative energy transfer
Mc Evoy, Niall; Duesberg, Georg; Bradley, Louise (2017)In this study highly efficient nonradiative energy transfer from semiconductor quantum dots to monolayer MoS 2 with an efficiency of ~99% is demonstrated. Although the energy transfer efficiency is close to unity, there ... -
Epitaxial lift-off of ZnSe based II-VI structures
Bradley, Louise; Hegarty, John (1995)The epitaxial lift-off technique is applied to II?VI based structures. Epilayers of 255 nm thickness containing quantum wells are lifted off their substrates and redeposited onto polyimide coated GaAs. The technique has ...