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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 65 for “"lattice dynamics"”.
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X-ray Studies of Lattice Dynamics
… populated phonon modes has been used to study lattice dynamics and phonon phase transitions in several systems. Several experiments are reviewed - the viability and accuracy of this method was established by establishing phonon dispersion curves (PDCs) in elemental systems including Si and Nb …
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Lattice dynamics of Chevrel phase compounds
… atom motions in these normal modes. Numerical lattice-dynamics calculations were performed. The calculation parameters were varied to fit the experimental data. The results of the calculations include descriptions of the motions of the atoms in the various normal modes, dispersion curves, and …
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Non-affine lattice dynamics of disordered solids
… to the theoretical framework of non-affine lattice dynamics the attention is focused on the analysis of disordered networks and lattices which serve as tractable model systems for real materials. Firstly, we discuss the static elastic response and the vibrational spectra of defective fcc …
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An investigation of lattice dynamics using waveguide arrays
… the evolution of the light mimics the complex dynamics of a quantum particle in a lattice. This mapping combined with the powerful capabilities of ultrafast laser inscription to precisely control the properties of the simulated lattice makes coupled optical waveguides a potent probe of …
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Fluxon lattice dynamics in the superconducting mixed state
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1997.
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Visualization of the Vortex Lattice Dynamics in Superfluid Helium
We study the lattice structure and dynamics of the quantized vortices in superfluid helium-4 using a new rotating experiment. This setup includes control of the entire apparatus from the rotating frame, installation of a new EMCCD camera that allows for imaging of nanoscale tracer particles, and …
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Lattice dynamics of zinc blende crystals with point impurities.
Thesis: Sc. D., Massachusetts Institute of Technology, Department of Nuclear Engineering, 1972
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Lattice Dynamics in Temperature-driven and Photo-induced Phase Transitions
… experiments can now resolved femtosecond atomic dynamics by using an ultrafast laser pulse to excite materials out of equilibrium and then track the Bragg or diffuse intensities with a time-resolved pulse of X-rays. However, the response of materials to the laser pulse is complex, necessitating …
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Lattice dynamics and electron/phonon interactions in epitaxial transition-metal nitrides
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2015-09-29 without embargo terms
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X-ray thermal diffuse scattering and its studies of lattice dynamics
X-ray scattering by lattice thermal vibrations give rise to thermal diffuse scattering (TDS). TDS contain valuable information about lattice dynamics of the scattering material. Historically, x-ray TDS was the first tool utilized by people in experimental determination of phonon dispersion …
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Femtosecond wavevector overtone spectroscopy of anharmonic lattice dynamics in ferroelectric crystals
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1997.
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Adaptive heterogeneous parallelism for semi-empirical lattice dynamics in computational materials science.
With the variability in performance of the multitude of parallel environments available today, the conceptual overhead created by the need to anticipate runtime information to make design-time decisions has become overwhelming. Performance-critical applications and libraries carry implicit …
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Ultrafast lattice dynamics in photoexcited nanostructures : femtosecond X-ray diffraction with optimized evaluation schemes
… the complex interplay between electron and lattice dynamics in nanostructures of perovskite oxides. Femtosecond hard X-ray pulses were utilized to probe the evolution of atomic rearrangement directly, which is driven by ultrafast optical excitation of electrons. The physics of complex …
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Applications of lattice dynamics theory : calculating vibrational entropy in alloys and dielectric losses in ceramics
This thesis applies the theory of lattice dynamics towards two applications: vibrational entropy in alloys and dielectric absorption in oxides. Vibrational entropies between ordered-L12 and disordered phases in the Au3Cu, Cu3Au, Cu3Pd, Pd3Cu, Cu3Pt, Au3Pd, and Pd3Au systems are calculated. This …
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Neutron scattering studies of the magnetism and lattice dynamics in La₂âx̳Srx̳CuO₄
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 1989.
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Influence of lattice dynamics on the ionic conductivity and stability of solid-state lithium-ion conductors
… insertion/removal in ion conductors based on lattice dynamics. By combining inelastic neutron scattering measurements with density function theory computation, greater lithium ion mobility was correlated with decreasing lithium vibration frequency that was quantified using a newly proposed …
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Influence of Electronic Structure and Lattice Dynamics on Oxygen Ion Transport in Solid-State Ionic Conductors
… entropy can be tuned by designing the phonon dynamics of these atoms. These results imply that a widely observed correlation between increasing pre-exponential factors and activation energy arises from coupling local electronic energy states and phonons. The results are extended to the …
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Molecular dynamics calculation of mean square displacement in alkali metals and rare gas solids and comparison with lattice dynamics
Molec ul ar dynamics calculations of the mean sq ua re displacement have been carried out for the alkali metals Na, K and Cs and for an fcc nearest neighbour Lennard-Jones model applicable to rare gas solids. The computations for the alkalis were done for several temperatures for temperature vol …
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Fast ion conduction in solid electrolyte materials: An investigation of the relationship between lattice dynamics, geometric frustration induced disorder, and ionic conductivity
The student, William Gustafson, accepted the attached license on 2020-07-21 at 14:32.
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Nuclear Forward-Scattering of Synchrotron Radiation From Krypton: First Observation and Application to the Study of Lattice Dynamics in Near-Monolayer Krypton-on-Graphite
… from Kr has been applied to study the lattice dynamics of near-monolayer Kr-on-graphite by measurement of the probability for recoil-free scattering, i.e., Lamb-Mossbauer factor, (f<sub>LM</sub>) as a function of both relative coverage on the substrate and sample temperature. This …
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