Sökning: "grating coupler"

Visar resultat 11 - 15 av 15 avhandlingar innehållade orden grating coupler.

1. 11. On diode-pumped solid-state lasers

   Författare :Jonas Hellström; Fredrik Laurell; Valdas Pasiskevicius; Klaus Petermann; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; near-infrared lasers; end-pumped lasers; Q-switching; erbium; ytterbium; GdCOB; KGW; KYW; Co:MALO; laser materials; thermal lensing; end-pumping; spectroscopy; conical refraction; volume Bragg gratings; holographic gratings; laser tuning; Physics; Fysik;

   Sammanfattning : The research that is presented in this thesis can be divided into two major parts. The first part concerns longitudinally pumped, bulk Er-Yb lasers. In these lasers, the main limitation is the thermal shortcomings of the phosphate glass host material. LÄS MER

3. 12. 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

4. 13. Silicon-based Photonic Devices : Design, Fabrication and Characterization

   Författare :Ziyang Zhang; Min Qiu; Thomas Koch; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Photonic Devices; Silicon Photonics; Parallel Computation; Nanofabrication; Electron Beam Lithography; Optical Characterisation; Optics; Optik;

   Sammanfattning : The field of Information and Communication Technologies is witnessing a development speed unprecedented in history. Moore’s law proves that the processor speed and memory size are roughly doubling each 18 months, which is expected to continue in the next decade. LÄS MER

5. 14. Nanosecond tandem optical parametric oscillators for mid-infrared generation

   Författare :Markus Henriksson; Fredrik Laurell; Gunnar Rustad; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nonlinear optics; optical parametric oscillators; quasi-phase matching; mid-infrared; linewidth narrowing; volume Bragg gratings.; Physics; Fysik;

   Sammanfattning : This thesis discusses a new scheme for generating radiation in the mid infrared spectral region, especially the 3.5-5 µm range. The scheme uses established Nd3+-lasers at 1.06 µm and down conversion in nonlinear optical crystals. LÄS MER

7. 15. 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