Sökning: "modulational instability"

Hittade 5 avhandlingar innehållade orden modulational instability.

  1. 1. Aspects of Wave Interaction in Nonlinear Media

    Författare :Björn Hall; [2005]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear Schrödinger equation; incoherent solitons; partial incoherence; nonlinear wave interaction; Gross-Pitaevskii equation; modulational instability; collective dynamics; Wigner transform; nonlinear guided waves; Bose-Einstein condensation;

    Sammanfattning : Selected aspects of various types of nonlinear wave interaction are investigated. These aspects are studied in terms of models described by Nonlinear Schrödinger equations, mainly analytically and numerically, but also experimentally. LÄS MER

  2. 2. Nonlinear Theory of Partially Coherent Optical Waves

    Författare :Tobias Hansson; [2011]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nonlinear optics; partial coherence; beam collapse; saturable logarithmic media; soliton interaction; dressing method; parabolic beams; Wigner transform; invariants; modulational instability;

    Sammanfattning : Nonlinear effects arise in optics as a consequence of the medium properties being modified by the presence of light. Of particular interest are situations where the effect of the nonlinearity can be described by an intensity dependent refractive index and the subsequent interplay with dispersion and diffraction. LÄS MER

  3. 3. Nonlinear Propagation of Partially Incoherent Light

    Författare :Lukasz Helczynski-Wolf; [2005]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : This thesis deals with consequences of partial incoherence on light propagation in nonlinear media. A new approach, based on the Wigner transform method, has beed developed and used to investigate several important problems in nonlinear light propagation. LÄS MER

  4. 4. Waves and instabilities in quantum plasmas

    Detta är en avhandling från Umeå : Fysik

    Författare :Shahid Ali; Umeå universitet.; [2008]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum mechanical effects; dusty plasma; linear and nonlinear waves; instabilities; nonlinear wave interactions; density gradients; magnetoplasmas.; NATURAL SCIENCES Physics Geocosmophysics and plasma physics Plasma physics; NATURVETENSKAP Fysik Geokosmofysik och plasmafysik Plasmafysik;

    Sammanfattning : The study of waves and instabilities in quantum plasmas is of fundamental importance for understanding collective interactions in superdense astrophysical objects, in high intense laser-plasma/solid-matter interactions, in microelectronic devices and metallic nanostructures. In dense quantum plasmas, there are new pressure laws associated with the Fermi-Dirac distribution functions and new quantum forces associated with the quantum Bohm potential and the Bohr magnetization involving electron ½ spin. LÄS MER

  5. 5. Nonlinear pulse propagation and saturation gain grating phenomena in optical fiber devices

    Detta är en avhandling från Institutionen för elektronisk systemkonstruktion

    Författare :Evgeny V. Vanin; KTH.; [1999]
    Nyckelord :;

    Sammanfattning : Nonlinear effects are known to influence the propagation ofoptical waves in fibers already at modest power levels. Thisprovides us with a unique tool to observe nonlinear phenomenaunder comparatively simple experimental conditions and alsoopens the door to numerous important applications. LÄS MER