Blow-up Dynamics and Orbital Stability for Inhomogeneous Dispersive Equations

This dissertation addresses the local-well posedness, singularity formation, and orbital stability of standing waves to inhomogeneous nonlinear dispersive equations. Inhomogeneous equations are equations with space-dependent coe <br/>cients, which account for the impurities of the propagating media or the presence of an outer potential. Despite...

Terahertz Raman laser based on silicon doped with phosphorus

Raman-type stimulated emission at frequencies between 5.0 and 5.2?THz as well as between 6.1 and 6.4?THz has been realized in silicon crystals doped by phosphorus donors. The Raman laser operates at around 5?K under optical excitation by a pulsed, frequency-tunable infrared free electron laser. The frequencies of the observed laser emission are...

Location of lanthanide impurity levels in the III-V semiconductor GaN

Knowledge from lanthanide spectroscopy on wide band gap (6–10?eV) inorganic compounds is used to understand and predict optical and electronic properties of the lanthanides in the III-V semiconductor GaN. For the first time the location of the 4fn ground state energy of each divalent and trivalent lanthanide ion relative to the valence and...

Novel structures and energy spectra of hydroxylated (SiO2)8-based clusters: Searching for the magic (SiO2)8O2H3? cluster

The prominent (SiO2)8O2H3? mass peak resulting from the laser ablation of hydroxylated silica, attributed to magic cluster formation, is investigated employing global optimization with a dedicated interatomic potential and density functional calculations. The low-energy spectra of cluster isomers are calculated for the closed shell clusters: ...

Potential model for tetrathiafulvalene based on inelastic neutron scattering and Raman spectra

Tetrathiafulvalene (TTF) is a key molecule in the family of charge-transfer salts of interest for their novel transport properties. The correspondence between transport property and electron-molecular vibration coupling requires that we understand the phonon density of states for these materials. Here we report the results of a low temperature...