Search for dissertations about: "BPM simulations"

Found 4 swedish dissertations containing the words BPM simulations.

  1. 1. Grating-Coupled Surface-Emitting Lasers -- Circular and Unstable-Resonator Geometries

    Author : Sigurgeir Kristjánsson; Chalmers University of Technology; []
    Keywords : laser beam focusing; grating coupled surface emitters; simulation; unstable resonator lasers; surface-emitting lasers; integrated optics; gratings; circular gratings; BPM simulations; laser resonators; semiconductor lasers; optical planar waveguide couplers; electron beam lithography;

    Abstract : This thesis deals with research in the field of grating-coupled surface-emitting lasers. The emphasis has been to study the modal behavior of lasers with two different resonator geometries: circular resonators and tapered unstable-resonators. READ MORE

  2. 2. Designs and simulations of silicon-based microphotonic devices

    Author : Daoxin Dai; Sailing He; Siegfried Janz; KTH; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electronics; waveguide; silicon-on-insulator SOI ; arrayed waveguide grating AWG ; Elektronik; Electronics; Elektronik;

    Abstract : The characteristics of a silicon-on-insulator (SOI) rib waveguide, including the bending loss of a multimode bent waveguide and the birefringence of a rib waveguide, are analyzed by using a finite-difference method (FDM). Based on a detailed analysis for a multimode bent waveguide, an appropriately designed multimode bent waveguide for reducing effectively the bending loss of the fundamental mode is realized. READ MORE

  3. 3. Simulation of Electro-Optic Modulators by a Time-Domain Beam-Propagation Method

    Author : Elin Solberg; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; time-domain beam-propagation method; finite element method; tensor products; computational electromagnetics; photonics; electro-optic modulators; finite element method;

    Abstract : Electro-optic modulators (EOMs) are components which convert electric signals to optical ones. They are needed, e.g., at the transmitter end of fiber-optic communication systems and in time-stretch analog-to-digital converters. READ MORE

  4. 4. Towards Discrete Element Modelling of Rock Drilling

    Author : Albin Wessling; Simon Larsson; Pär Jonsén; Jörgen Kajberg; Bengt Wikman; Luleå tekniska universitet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DEM Rock Dynamic Drilling; Solid Mechanics; Hållfasthetslära;

    Abstract : The method of percussive rotary drilling is recognized as the most efficient method for hard rock drilling. Despite the clear advantages over conventional rotary meth-ods, there are still uncertainties associated with percussive rotary drilling. READ MORE