Sökning: "self-focussing"

Hittade 2 avhandlingar innehållade ordet self-focussing.

1. 1. Non-Linear Spatio-Temporal Dynamics of Optical Beams and Pulses in Kerr and Ionizable Media

   Författare :Manuel López Quiroga Teixeiro; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; self-focussing; wave-breaking; optical Kerr effect; autowaves; fast adiabatic compression; non-linear modes conversion; non-linear optics; blue-shift; solitons; full wave numerical simulations; optical fibers; ionization non-linearities; pulse compressioni;

   Sammanfattning : The present thesis includes results of several investigations concerning the propagation of optical pulses in optical fibers and spatio-temporal beams in optical Kerr media and ionizable media. Both numerical and analytical methods play an important role in the investigations. LÄS MER

3. 2. Opening New Radio Windows and Bending Twisted Beams

   Författare :Erik Nordblad; Thomas B. Leyser; Kristof Stasiewicz; Vladimir Pavlenko; Paul A. Bernhardt; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Orbital angular momentum; Hall effect; Nonparaxial beam; Geometrical optics; High frequency radio waves; Ray tracing; Magnetic zenith effect; Ionospheric irregularities; Wave propagation; Fysik med inriktning mot rymd- och plasmafysik; Physics with specialization in Space and Plasma Physics;

   Sammanfattning : In ground based high frequency (HF) radio pumping experiments, absorption of ordinary (O) mode pump waves energises the ionospheric plasma, producing optical emissions and other effects. Pump-induced or natural kilometre-scale field-aligned density depletions are believed to play a role in self-focussing phenomena such as the magnetic zenith (MZ) effect, i. LÄS MER