Sökning: "quasi-phasematching"

Visar resultat 1 - 5 av 8 avhandlingar innehållade ordet quasi-phasematching.

  1. 1. Nanosecond optical parametric oscillators and amplifiers based on periodically poled KTiOPO4

    Författare :Jonas Hellström; KTH; []
    Nyckelord :optical parametric oscillators; optica parametric amplifiers; quasi-phasematching; KTiOPO4; nonlinear optics; frequency conversion; periodic electric field poling; ferroelectrics; high-order second harmonic generation; electro-optic effect;

    Sammanfattning : Optical parametric oscillators (OPOs) and optical parametricamplifiers (OPAs) constitute a class of optical frequencyconverting devices that have many possible applications, e.g.in range finding, molecular spectroscopy and medicine. LÄS MER

  3. 2. Fabrication and characterization of periodically poled KTB and RB-doped KTB for applications in the visible and UV

    Författare :Shunhua Wang; Fredrik Laurell; Peter Smith; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nonlinear optics; second-harmonic generation; quasi-phasematching; type-I QPM SHG; type-II QPM SHG; KTP; RKTP; periodic electric-field poling; Physics; Fysik;

    Sammanfattning : This thesis deals with the fabrication and the characterization of periodically-poled crystals for use in lasers to generate visible and UV radiation by second-harmonic generation (SHG) through quasi-phasematching (QPM). Such lasers are of practical importance in many applications like high-density optical storage, biomedical instrumentation, colour printing, and for laser displays. LÄS MER

  4. 3. Laser diode systems for photodynamic therapy and medical diagnostics

    Författare :Eva Samsöe Andersen; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quasi-phasematching; photodynamic therapy; laser-induced fluorescence; medical laser systems.; Histology; cytochemistry; histochemistry; tissue culture; Histologi; Laserteknik; Laser technology; cytokemi; histokemi; vävnadskultur; Diagnostik; Diagnostics; second harmonic generation; pulsed lasers; spatial filtering; Diode lasers; optical feedback; Fysicumarkivet A:2004:Samsöe Andersen;

    Sammanfattning : This work concerns techniques for improvement of the coherence properties of diode lasers so that they may be used in two specific medical applications: (Interstitial) photodynamic therapy (PDT) and laser-induced fluorescence diagnostics. In the first application, spatial coherence is crucial, since the treatment light should be delivered through relatively thin optical fibers to optimize treatment and to facilitate minimally invasive treatment. LÄS MER

  5. 4. Quasi-Phasematched nonlinear processes in KTiOPO4 isomorphs

    Författare :Anna Fragemann; KTH; []
    Nyckelord :nonlinear optics; optical parametric oscillator; optical parametric amplifier; KTiOPO4; RbTiOPO4; quasi-phasematched; electric field poling;

    Sammanfattning : This thesis explores the use of nonlinear crystals from theKTiOPO4(KTP) family with the aim to extend the possibleapplications for laser sources and to gain more knowledge aboutthe material’s benefits and limits. The work focussed onoptical parametric oscillators (OPOs) and optical parametricamplifiers (OPAs), which employ second order nonlinearprocesses. LÄS MER

  7. 5. Fabrication of periodically poled crystals from the KTP family and their applications in nonlinear optics

    Författare :Håkan Karlsson; KTH; []
    Nyckelord :;

    Sammanfattning : Quasi-phasematched (QPM) nonlinear optical frequencyconversion is a powerful tool in the development of new lasersources, by providing high conversion efficiency and largeflexibility in terms of output wavelengths.QPM structures are preferably implemented in bulk crystalsbe periodic electric field poling. LÄS MER