Sökning: "bragg"

Visar resultat 16 - 20 av 74 avhandlingar innehållade ordet bragg.

  1. 16. Applications of monolithic fiber interferometers and actively controlled fibers

    Författare :Patrik Rugeland; Fredrik Laurell; Walter Margulis; Miguel Andrés; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Fiber; fiber Bragg grating; micro-structured fiber; add drop multiplexer; fiber interferometer; microwave photonics; temperature sensor;

    Sammanfattning : The objective of this thesis was to develop applications of monolithic fiber devices and actively controlled fibers. A special twin-core fiber known as a ‘Gemini’ fiber was used to construct equal arm-length fiber interferometers, impervious to temperature and mechanical perturbations. LÄS MER

  2. 17. Compact solid-state lasers in the near-infrard and visible spectral range

    Författare :Kai Seger; Fredrik Laurell; Uwe Griebner; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; volume Bragg gratings; single-longitudinal-mode laser; laser tuning; Q-switching; mode-locking; carbon nanotubes; semiconductor lasers; neodymium; ytterbium; nonlinear optics; KTP;

    Sammanfattning : The subject of this thesis is the exploration of new concepts for compact solid-state lasers in the visible and near-infrared spectral range using new components such as volume Bragg gratings for wavelength stabilisation and wavelength tuning. Also single-walled carbon nanotubes for mode-locking and Q-switching of lasers have been studied. LÄS MER

  3. 18. Durability of Embedded Fibre Optic Sensors in Composites

    Författare :Klas Levin; KTH; []
    Nyckelord :composites; fibre optic sensor; embedded EFPI sensor; bragg grating sensor; durability. Fatique; impact strain measurement;

    Sammanfattning : This thesis concerns various aspects of the durability offibre optic sensors embedded in composite. Since repair orreplacement of embedded sensors is not generally possible, thefunctional reliability of embedded sensors is one of the mostimportant prerequisites for successful use. LÄS MER

  4. 19. Photosensitivity, chemical composition gratings and optical fiber based components

    Författare :Michael Fokine; KTH; []
    Nyckelord :optical fibers; fiber bragg gratings; photosensitivity; thermal stability; NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : The different topics of this thesis include high-temperaturestable fiber Bragg gratings, photosensitivity and fiber basedcomponents. Fiber Bragg gratings (FBG) are wavelength dispersiverefractive index structures manufactured through UV exposure ofoptical fibers. LÄS MER

  5. 20. Technology for photonic components in silica/silicon material structure

    Författare :Lech Wosinski; KTH; []
    Nyckelord :silica-on-silicon technology; PECVD; plasma deposition; photonic integrated circuits; planar waveguide devices; UV Bragg gratings; photosensitivity; arrayed waveguide gratings; multimode interference couplers; add-drop multiplexers;

    Sammanfattning : The main objectives of this thesis were to develop a lowtemperature PECVD process suitable for optoelectronicintegration, and to optimize silica glass composition forUV-induced modifications of a refractive index in PECVDfabricated planar devices. The most important achievement isthe successful development of a low temperature silicadeposition, which for the first time makes it is possible tofabricate good quality low loss integrated components whilekeeping the temperature below 250oC during the entirefabrication process. LÄS MER