Browsing by Author "Lunney, James"
Now showing items 1-10 of 10
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Anisotropic ferromagnetism in substituted zinc oxide
Lunney, James; Coey, John; Venkatesan, Munuswamy (2004)The high-temperature ferromagnetism in doped zinc oxide films was discussed. A connection between the electronic structure of (Zn 1-xMx)O and its ferromagnetic properties was found. A new source of magnetism in these oxides, ... -
Conical diffraction intensity profiles generated using a top-hat input beam
Donegan, John; Lunney, James; Eastham, Paul; Mc Closkey, David (2014) -
Device for inductive heating and focusing of laser produced plasma
Lunney, James (2019)The design and implementation of a pulsed magnetic induction device used to heat and focus a laser produced plasma in vacuum is described. Imaging of the plasma light emission and optical spectroscopy show that the UV/visible ... -
GaN resonant cavity light-emitting diodes for plastic optical fibre applications
Lunney, James; Donegan, John; Bradley, Louise (2004)The optical designs of resonant GaN light-emitting diodes (LEDs) have been determined for maximum extraction efficiency into typical plastic optical fiber of numerical aperture 0.5. An optimum extraction efficiency of 3.9% ... -
Interaction of Surface Plasmons with CdTe quantum dot excitons
Lunney, James; Donegan, John; Bradley, Louise; Donnelly, Tony; Vamsi, Komarala; Rakovich, Yury; Doggett, B.; Gaponik, Nikolai; Susha, A. (2005)A 5-fold enhancement in the luminescence of CdTe nanocrystal quantum dots (QDs) is observed when they are placed in proximity to a nanostructured Au film deposited by pulsed laser deposition technique. No enhancement is ... -
Metal Nanoparticle Film Deposition by Femtosecond Laser Ablation at Atmospheric Pressure
Lunney, James (2020)Nanoparticle gold films were deposited using femtosecond laser ablation in argon at atmospheric pressure in an arrangement where a flat Au target was irradiated through a transparent substrate in close proximity. Spatially ... -
Modelling of Extraction Efficiency of GaN-Based Resonant Cavity Light Emitting Diodes Emitting at 510 nm
Bradley, Louise; Donegan, John; Lunney, James (2002)The design of GaN resonant cavity light emitting diodes (RCLEDs) emitting at 510 nm is optimised for maximum extraction efficiency into numerical apertures (NAs) of 1.0 and 0.5. The optimisation is performed as a function ... -
Optical design of GaN resonant cavity LEDs emitting at 510 nm for use in plastic optical fibre applications
Lunney, James; Donegan, John; Bradley, Louise (2003)The optimized optical design of GaN resonant cavity light emitting didoes (RCLEDs) emitting at 510nm for maximum extraction efficiency into numerical apertures (NAs) of 1.0 (total emission) and 0.5 (typical plastic optical ... -
Photoresponsivity enhancement in monolayer MoS<inf>2</inf> by rapid O<inf>2</inf>:Ar plasma treatment
Zhang, Hongzhou; Lunney, James (2019)We report up to ten-fold enhancement of the photoresponsivity of monolayer molybdenum disulfide (MoS2) by treatment with O2:Ar (1:3) plasma. We characterize the surface of plasma-exposed MoS2 by TEM, Raman, and PL mapping ... -
Reactive Plasma N-Doping of Amorphous Carbon Electrodes: Decoupling Disorder and Chemical Effects on Capacitive and Electrocatalytic Performance
Lunney, James; Perova, Tatiana; Colavita, Paula (2020)Nitrogen-free amorphous carbon thin films prepared via sputtering followed by graphitization, were used as precursor materials for the creation of N-doped carbon electrodes with varying degrees of amorphization. Incorporation ...