Search for dissertations about: "optical focusing"

Showing result 1 - 5 of 72 swedish dissertations containing the words optical focusing.

2. 1. Nonlinear Propagation of Optical Pulses and Beams

   Author : Magnus Karlsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; self-phase modulation; optical wave breaking; paraxial-ray approximation; stimulated Raman scattering; nonlinear Schrödinger equation; optical collapse; modulational instability; higher-order dispersion; optical fibers; saturable nonlinearity; Kerr-nonlinearity; self-trapping; group-velocity dispersion; optical solitons; self-focusing;

   Abstract : The propagation of optical beams and pulses under the influence of nonlinear effects is characterized by a rich variety of phenomena and many potentially important applications. We analyse two main topics in this context: nonlinear beam propagation, and nonlinear pulse propagation in optical fibers. READ MORE

4. 2. Provisioning Strategies for Transparent Optical Networks Considering Transmission Quality, Security, and Energy Efficiency

   Author : Amornrat Jirattigalachote; Lena Wosinska; Paolo Monti; Biswanath Mukherjee; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; transparent optical networks; routing and wavelength assignment; physical-layer impairments; signal quality; differentiation of services; physical-layer attacks; power equalizers; Greedy Randomized Adaptive Search Procedure GRASP ; green networks; energy awareness; dedicated path protection; shared path protection; survivable WDM networks;

   Abstract : The continuous growth of traffic demand driven by the brisk increase in number of Internet users and emerging online services creates new challenges for communication networks. The latest advances in Wavelength Division Multiplexing (WDM) technology make it possible to build Transparent Optical Networks (TONs) which are expected to be able to satisfy this rapidly growing capacity demand. READ MORE

5. 3. Optical manipulation and heating of gold nanoparticles near interfaces

   Author : Daniel Andrén; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LSPR spectroscopy; particle-surface separation distance; thermal reshaping; TIRM; nanomotor; plasmonics; photothermal effects; Brownian dynamics; gold nanorod; optical tweezers;

   Abstract : By focusing laser light to small volumes, its momentum can be used to trap and manipulate objects in the size range from cells down to single atoms. Devices using this effect are called optical tweezers, and have found use in measuring and applying minuscule forces and torques, contributed to deepening our knowledge of molecular motors, unraveling the mechanics of cells and DNA, and better understand statistical mechanics and hydrodynamic interactions at the nanoscale. READ MORE

6. 4. Simulations of directionality effects and optical forces in plasmonic nanostructures

   Author : Vladimir Miljkovic; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Comsol multiphysics; optical forces; nanoparticles; nanowires; DDA; surface plasmons; Green’s function; Mie theory;

   Abstract : With the rapid development of nanoscience and nanotechnology, surface plasmonics based on metal nanoparticles and nanostructures gain increasing interest, not only for fundamental scientific studies, but also for optical and sensor applications. At the nanoscale, the physical and chemical properties of metal particles, especially their optical properties, strongly depend on size and shape, as well as on the surrounding media and structures. READ MORE

7. 5. Focusing properties of attosecond pulses

   Author : Maria Hoflund; Atomfysik; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : The discovery of high-order harmonic generation (HHG) has made it possible to see the electron dynamics on their natural time scale, attoseconds. In the HHG process, a femtosecond infrared (IR) laser pulse is converted into a train of attosecond pulses in the extreme ultraviolet (XUV), but with a very low conversion efficiency. READ MORE