Browsing Physics and Astronomy by Issue Date
Now showing items 1-20 of 683
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The electrostatic potential in a finite ionic crystal
(University of Waterloo, 1972-11-01)This thesis is written in two parts. In Part One, we develop a new method for evaluating three dimensional lattice summations and apply it to the evaluation of the electrostatic potential of a finite ionic crystal. We then ... -
Electric-field-dependent variable-range hopping conductance in quasi-two-dimensional systems: Application to PrBa2Cu3O7-y-based superconductor–normal-metal–superconductor junctions
(American Physical Society, 1996-03)We have calculated the hopping conductivity of quasi-two-dimensional systems by using the variable-range hopping conduction mechanism in the presence of an electric field. We considered that the localized states are randomly ... -
Electric-field-dependent variable-range hopping conduction in PrBa2Cu307-y
(Taylor & Francis, 1997-02)The variable-range hopping conductivities of quasi-two-dimensional systems in electric fields were calculated for the cases of both constant and energy-dependent densities of states. The localized states were considered ... -
Magnetoconductance due to variable-range hopping in quasi-two-dimensional systems: Application to PrBa2Cu3O7-delta
(American Physical Society, 1998-01)In this paper, we have developed a theory of magnetoconductance (magnetoresistance) due to variable-range hopping for quasi-two-dimensional systems. We have included the effect of electric fields on the calculation of the ... -
Small-polaron variable-range hopping in quasi-two-dimensional materials: application to PrBa2Cu3-xGax07-y
(Taylor & Francis, 1999-01)We have developed a theory for variable-rangehopping (VRH) due to small polarons in quasi-two-dimensionalsystems at high temperatures.We included the effects of temperature, electric fields, magnetic fields and scattering ... -
A Quasilocal Hamiltonian for Gravity with Classical and Quantum Applications
(University of Waterloo, 2000)I modify the quasilocal energy formalism of Brown and York into a purely Hamiltonian form. As part of the reformulation, I remove their restriction that the time evolution of the boundary of the spacetime be orthogonal ... -
Predicting the Mesophases of Copolymer-Nanoparticle Composites
(American Association for the Advancement of Science, 2001)The interactions between mesophase-forming copolymers and nanoscopic par- ticles can lead to highly organized hybrid materials. The morphology of such composites depends not only on the characteristics of the copolymers, ... -
Modelling Quantum Well Lasers
(University of Waterloo, 2002)In this thesis, two methods to model quantum well lasers will be examined. The first model is based on well-known techniques to determine some of the spectral and dynamical properties of the laser. For the spectral ... -
Entropically Driven Formation of Hierarchically Ordered Nanocomposites
(American Physical Society, 2002)Using theoretical models, we undertake the first investigation into the rich behavior that emerges when binary particle mixtures are blended with microphase-separating copolymers. We isolate an example of coupled self-assembly ... -
Block Copolymer-Directed Assembly of Nanoparticles: Forming Mesoscopically Ordered Hybrid Materials
(American Chemical Society, 2002)Mixtures of diblock copolymers and nanoscopic spherical particles can yield well-ordered hybrid materials, which can be used for separation processes, catalysis, and optoelectronic applications. Predicting the morphologies ... -
Effect of Nanoscopic Particles on the Mesophase Structure of Diblock Copolymers
(American Chemical Society, 2002)Introduction. The fabrication of novel biomimetic photonic and electronic materials requires the manipulation of both organic and inorganic materials at the nanometer length scale. One possible means of achieving this level ... -
Characterisation and Optimization of Ultrashort Laser Pulses
(University of Waterloo, 2003)The ultrafast optical regime is defined, as it applies to laser pulses, along with a brief introduction to pulse generation and characterisation technologies. A more extensive description of our particular amplified ... -
Physics in Higher-Dimensional Manifolds
(University of Waterloo, 2003)In this thesis, we study various aspects of physics in higher-dimensional manifolds involving a single extra dimension. After giving some historical perspective on the motivation for studying higher-dimensional theories ... -
HIGH RESOLUTION MICROWAVE SPECTROSCOPY OF ULTRA COLD RYDBERG ATOMS AS A PROBE OF ELECTRIC AND MAGNETIC FIELDS
(University of Waterloo, 2003)In highly excited Rydberg atoms, the excited electron is in a large, loosely bound orbit. Hence, in contrast with the ground states, the Rydberg states are very sensitive to external electric field and can be ionized in ... -
Self-assembly of a binary mixture of particles and diblock copolymers
(Royal Society of Chemistry, 2003)Using theoretical models, we undertake the first investigation into the synergy and rich phase behavior that emerges when binary particle mixtures are blended with microphase- separating copolymers. We isolate an example ... -
Self-Assembly of Amphiphilic Nanoparticle-Coil “Tadpole” Macromolecules
(American Chemical Society, 2004)None. -
Origins of Elastic Properties in Ordered Block Copolymer/Nanoparticle Composites
(American Chemical Society, 2004)We predict a diblock copolymer melt in the lamellar phase with added spherical nanoparticles that have an affinity for one block to have a lower tensile modulus than a pure diblock copolymer system. This weakening is due ... -
Ordering mechanisms in triblock copolymers
(American Physical Society, 2004)The ordering mechanisms for an ABC triblock copolymer system are studied using self-consistent field theory. We find a two-phase mechanism, similar to what has been suggested experimentally two-step mecha- nism. Analysis ... -
Improved convergence in block copolymer self-consistent field theory by Anderson mixing
(American Institute of Physics, 2004)A modification to real space polymeric self-consistent field theory algorithms that greatly improves the convergence properties is presented. The method is based on Anderson mixing (D. G. Anderson, J. Assoc. Comput. Mach. ... -
Self-Assembly of Amphiphilic Nanoparticle-Coil “Tadpole” Macromolecules
(American Chemical Society, 2004)There has been considerable fascination with the self-assembling behavior of amphiphilic chainlike molecules that range from short-chain surfactants to high molecular weight block copolymers. The self-assembly of simple ...