Sökning: "optical feedback"

Visar resultat 11 - 15 av 61 avhandlingar innehållade orden optical feedback.

  1. 11. Waveguide structures for efficient nonlinear optical conversion and distributed-feedback laser resonators

    Författare :Cristine C. Kores; Fredrik Laurell; Azzedine Boudrioua; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Optics and Photonics; Optik och fotonik;

    Sammanfattning : Integrated optical devices enable the development of miniaturized componentswith increased functionality, mechanical stability, robustness and reducedcost. Integrated devices that generate, manipulate and detect light enable opticalsystems that could not be implemented otherwise, at the vanguard ofboth technology and fundamental research. LÄS MER

  3. 12. Continuous-filtering Vernier spectroscopy

    Författare :Chuang Lu; Aleksandra Foltynowicz; Ove Axner; Wei Ren; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; spectroscopy; spectrometer; laser; optical frequency comb; optical cavity; NIR; MIR; flame; robust; time resolution; spectrum; fysik; Physics;

    Sammanfattning : Continuous-filtering Vernier spectroscopy (CF-VS) is a laser-based detection technique that combines the broad spectral coverage of an optical frequency comb (OFC) with the enhanced interaction length provided by an optical cavity. The resonances of the cavity filter the OFC to a small group of comb modes that probe the transitions of the species present in the cavity. LÄS MER

  4. 13. Tandem optical parametric oscillators using volume Bragg grating spectral control

    Författare :Markus Henriksson; Fredrik Laurell; Hiromasa Ito; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; optical parametric oscillators; mid-infrared; volume Bragg gratings; PPKTP; ZGP; nonlinear optics; narrowband OPO; Physics; Fysik;

    Sammanfattning : This thesis describes research on near degenerate quasi phase-matched opticalparametric oscillators (OPO) where volume Bragg gratings (VBG) are used toproduce narrow oscillation bandwidth. These OPOs are then used to pump a secondOPO to generate mid-infrared radiation. The atmospheric transmission windows in the 3. LÄS MER

  5. 14. Optical Guiding and Feedback Structures in GaN-Based Vertical-Cavity Surface-Emitting Lasers

    Författare :Seyed Ehsan Hashemi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The Vertical-Cavity Surface-Emitting Laser (VCSEL) made from GaAs-based materials is an established infrared light source, and is produced in large volumes for short-distance optical links, computer mice, and thermal processing systems. A wide range of applications, such as high-resolution printing, general lighting, and biomedical diagnosis and treatment could benefit from using a VCSEL with blue or ultraviolet emission. LÄS MER

  7. 15. Optical Guiding and Feedback in Gallium Nitride Based Vertical Cavity Surface Emitting Lasers

    Författare :Seyed Ehsan Hashemi; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antiguiding; vertical-cavity surface-emitting laser; gallium nitride laser; TiO2 high contrast grating;

    Sammanfattning : The gallium-nitride (GaN) semiconductor material has been the core of the revolutionary breakthroughs during the last two decades in the lighting industry, by enabling manufacturing of efficient blue light emitting diodes (LEDs), for which the 2014 Nobel prize in physics was awarded. The GaN technology has further led to violet edge-emitting lasers (EELs), enabling the Blu-ray disk technology, and also to the commercialization of directly green emitting EELs. LÄS MER