Physics (Theses and Dissertations): Recent submissions

Now showing items 221-240 of 458

    • Thermo and electro-optical analysis of polymer dispersed liquid crystal systems 

      Petti, Lucia (Trinity College (Dublin, Ireland). School of Physics, 2002)
      The objective of the work performed in this thesis is to prepare Polymer Dispersed Liquid Crystal (PDLC) systems under optimised preparation conditions and with improved liquid crystal/polymer composition for thermo-and ...

    • A study of the film growth environment in pulsed laser deposition of gallium nitride 

      O'Mahony, Donagh (Trinity College (Dublin, Ireland). School of Physics, 2004)
      This thesis describes a study of the deposition requirements for growth of stoichiometric GaN thin films using pulsed laser deposition. Growth has been carried out using either ceramic GaN or metal (solid and liquid) Ga ...

    • Nonlinear optical extinction in polymer-carbon nanotube and phthalocyanine systems 

      O'Flaherty, Seán Martin (Trinity College (Dublin, Ireland). School of Physics, 2003)
      The work presented in this thesis is based on experimental measurements of nonlinear optical extinction or optical limiting of nanosecond laser pulses by phthalocyanine and polymer-carbon nanotube systems. The nonlinear ...

    • Towards a parameter-free theory for electrochemical process at the nano-scale 

      KUMAR, ASHWINEE (Trinity College Dublin. School of Physics. Discipline of Physics, 2019)
      The mass and charge distribution at electrochemical interfaces plays a key role in driving electrochemical phenomena. However, in spite of its importance, even the structure of the Pt/water interface under bias, the most ...

    • Exchange coupling in CaMnO3and LaMnO3 : an ab initio study 

      Nicastro, Marco (Trinity College (Dublin, Ireland). School of Physics, 2003)
      This thesis is a study of the magnetic properties of a class of compounds known as manganites. They possess many peculiar properties which make them an interesting field of investigation for both experimentalists and ...

    • Numerical investigations of magnetic field effects on electrodeposition 

      Ní Mhíocháin, Teresa (Trinity College (Dublin, Ireland). School of Physics, 2002)
      Electrodeposits are fractal in nature when grown in a flat electrochemical cell, in which an aqueous solution of salt of a metal such as Cu, Zn or Ag is held between an anode and cathode by two flat sheets of perspex. These ...

    • Surface studies of the Fe/Mo(110) and Fe/W(100) epitaxial systems 

      Murphy, Shane (Trinity College (Dublin, Ireland). School of Physics, 2001)
      This thesis describes the investigation of ultrathin Fe film growth on the Mo(110) and W(100) surfaces, using scanning tunneling microscopy (STM), low-energy electron diffraction (LEED) and Auger electron spec­troscopy ...

    • A miroscopic and spectroscopic characterisation of nanotube/conjugated polymer interactions 

      McCarthy, Brendan (Trinity College (Dublin, Ireland). School of Physics, 2001)
      A composite material of a conjugated polymer and carbon nanotubes has been developed. The conjugated polymer is poly (p-phenylenevinylene-co-2,5-dioctyloxy-m-phenylenevinylene) (PmPV), a polymer significant for its ...

    • Surface reconstructions of Fe3 O4 (001) 

      Mariotto, Guido (Trinity College (Dublin, Ireland). School of Physics, 2002)
      In this thesis, the (001) surface of magnetite artificial single crystals has been studied using low-energy electron diffraction (LEED), Auger electron spectroscopy (AES) and Scanning Tunneling Microscopy (STM). STM ...

    • New conjugated polymers : Synthesis, characterisation and applications 

      Maier, Stefanie (Trinity College (Dublin, Ireland). School of Physics, 2000)
      A series of conjugated polymers related to poly (phenylenevinylene) have been synthesised and characterised. These polymers contain various substitution patterns. Octyloxy side-chains were attached to the arylene units of ...

    • Pulse formation and dynamics in self-pulsating semiconductor laser diodes 

      Lynch, Stephen A. (Trinity College (Dublin, Ireland). School of Physics, 2000)
      Self-pulsating lasers emitting at 800 nm are used in compact disc (CD) players because their low coherence makes them relatively insensitive to optical feedback. The ever increasing demand for higher capacity storage on ...

    • Optical and electrical properties of modified conjugated polymer thin films 

      Lipson, Malcolm Stephen (Trinity College (Dublin, Ireland). School of Physics, 2003)
      The ability to control both the spectral and electrical stability of polymer light emitting devices are just two of the parameters that are paramount to their commercial viability. The presence of water vapour and oxygen ...

    • Polymeric waveguides for use as solid state laser materials 

      Kretsch, Kevin P. (Trinity College (Dublin, Ireland). School of Physics, 2000)
      The work presented is intended to identify promising candidate materials for use as solid state lasers utilising planar optical waveguides, and to gain an insight into the physical processes that may be controlled through ...

    • Mechanical properties of carbon nanotube polymer composites 

      Lahr, Bernd (Trinity College (Dublin, Ireland). School of Physics, 2002)
      In this study the production and optimisation of carbon nanotubes using the arc discharge method was investigated. The soot produced was analysed for the nanotube content. To remove the nanotubes from the soot a novel ...

    • Scanning near-field microscopy of microwave circuits 

      Kantor, Roman (Trinity College (Dublin, Ireland). School of Physics, 2002)
      The topic of this thesis is the development and testing of measurement techniques for high resolution imaging of the field induced by microwave circuits in the near-field region. The theoretical aspects of the near-field ...

    • Paramagnetic defects in thin carbon films 

      Jones, Benjamin James (Trinity College (Dublin, Ireland). School of Physics, 2003)
      This thesis is an investigation into paramagnetic defects in thin carbon films, their nature and the effects of deposition parameters and post deposition treatments. Electron paramagnetic resonance (EPR) is used to examine ...

    • Optical impedance matching studied with Scanning Near-Field Optical Microscopy 

      Gademann, Anselm (Trinity College (Dublin, Ireland). School of Physics, 2003)
      This thesis is a study of reflection-mode Scanning Near-Field Optical Microscopy (SNOM). A microscope was built for non-invasive imaging of samples, with optical resolutions better than the diffraction limit. The microscope ...

    • Organic light-emitting diodes and photovoltaic devices: Incorporation of carbon nanotubes as charge transport media 

      Fournet, Patrick (Trinity College (Dublin, Ireland). School of Physics, 2003)
      The effects of incorporating multi-walled carbon nanotubes (MWNT) in two existing functional organic devices : organic light emitting diodes (OLEDs) and organic solar cells have been studied. Single layer OLEDs and organic ...

    • A dynamic study of cavity polaritons 

      Dunbar, L. A. (Trinity College (Dublin, Ireland). School of Physics, 2002)
      Strong coupling between an atom and a cavity field is a well established phenomenon in the field of cavity quantum electrodynamics. However it was not until 1992 that improvements in growth technology resulted in the advent ...

    • Localized basis approach to many-body effects and dielectric response 

      Hogan, Conor David (Trinity College (Dublin, Ireland). School of Physics, 2001)
      This thesis is a study of the optical and dielectric properties of semiconductors and insulators, and of the way in which these properties provide insight into the microscopic response of the interacting system. The central ...