Sökning: "Backward second-harmonic"

Hittade 4 avhandlingar innehållade orden Backward second-harmonic.

  1. 1. Backward and Forward Nonlinear Optical Processes in Potassium Titanyl Phosphate

    Författare :Kjell Martin Mølster; Fredrik Laurell; Valdas Pasiskevicius; Ulf L. Österberg; Stefano Taccheo; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; QPM; PPKTP; Nonlinear Optics; Backward second-harmonic; BWOPO; OPO; parametric devices; QPM; Ickelinär Optik; BWOPO; OPO; PPKTP; QPM; kvasifasematching; ikkelinæer optikk; bakovervendt parametrisk oscillator; optisk parametrisk oscillator; PPKTP; Optics and Photonics; Optik och fotonik; Physics; Fysik;

    Sammanfattning : Second-order nonlinear optical processes generate radiation across a broad spectrum, including UV and the far-infrared. In this thesis, new light sources in the near(NIR) and mid infrared (MIR) using three-wave mixing geometries in periodically poled potassium titanyl phosphate (PPKTP) is studied. LÄS MER

  3. 2. Domain engineering in KTiOPO4

    Författare :Carlota Canalias; Fredrik Laurell; Benoît Boulanger; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quasi-phase matching; KTiOPO4; ferroelectric domains; atomic force microscopy; periodic electric field poling; polarization switching; second harmonic generation; Optical physics; Optisk fysik;

    Sammanfattning : Ferroelectric crystals are commonly used in nonlinear optics for frequency conversion of laser radiation. The quasi-phase matching (QPM) approach uses a periodically modulated nonlinearity that can be achieved by periodically inverting domains in ferroelectric crystals and allows versatile and efficient frequency conversion in the whole transparency region of the material. LÄS MER

  4. 3. Quasi-phase matched devices in Rb-doped KTiOPO4: counterpropagating nonlinear interactions, domain dynamics, and waveguides

    Författare :Patrick Mutter; Carlota Canalias; Christopher Phillips; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

    Sammanfattning : Abstract Nonlinear interactions involving counterpropagating photons are gaining much attention in classical and quantum optics due to their unique properties that are very difficult, if not impossible, to realize in conventional co-propagating three-wave mixing. However, the large phase mismatch between the interacting waves demands an unnaturally large material birefringence or high-quality quasi-phasematched (QPM) devices with sub-µm periods. LÄS MER

  5. 4. QPM Devices in KTA and RKTP

    Författare :Andrius Zukauskas; Carlota Canalias; Moti Katz; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; QPM; periodic poling; KTP;

    Sammanfattning : Even though KTiOPO4 (KTP) is considered to be one of the best nonlinear materials for quasi phase matched (QPM) frequency conversion in the visible and the near-infrared spectral regions, its use is often limited by poor material homogeneity, high ionic conductivity, a considerable linear absorption and photochromatic damage. On the other hand, the improved material homogeneity and the lower ionic conductivity of bulk Rb-doped KTP (RKTP) make this material an ideal alternative for fabrication of fine-pitch QPM gratings, while the arsenate isomorph KTiOAsO4 (KTA) promises a better performance in the green spectral region and adds the advantage of a wider transparency window in the infrared. LÄS MER