Sökning: "Valdas Pasiskevicius"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden Valdas Pasiskevicius.

1. 1. Energy scaling of infrared nanosecond optical parametric oscillators and amplifiers based on Rb:KTiOPO4

   Författare :Riaan Stuart Coetzee; Valdas Pasiskevicius; Gunnar Rustad; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

   Sammanfattning : High-energy, narrowband, nanosecond pulsed mid-infrared sources centred on 2 μm are requiredin applications in remote sensing, standoff detection and pollution monitoring using LIDARs.Currently, space-borne LIDAR missions are under development by major space agencies aroundthe world for active measurements of the atmospheric gas constituents and their dynamics. LÄS MER

3. 2. 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

4. 3. Optical Parametric Devices in Periodically Poled LiTaO3

   Författare :Martin Levenius; Katia Gallo; Valdas Pasiskevicius; Giuseppe Leo; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nonlinear optics; parametric processes; frequency downconver-sion; quasi-phase matching; LiTaO3; broadband downconversion; quadratic cascading; nonlinear photonic crystals; twin-beam generation;

   Sammanfattning : Optical parametric frequency conversion based on quasi phase matching (QPM) in nonlinear optical crystals is a powerful technique for generating coherent radiation in wavelength ranges spanning from the mid-infrared (mid-IR) to the blue, displaying low thermal load and high efficiency.This thesis shows how QPM in one- (1D) or two-dimensional (2D) lattices can be employed to engineer novel devices for parametric downconversion in the IR, af-fording freedom in designing both spectral and angular properties of the parametric output. LÄS MER

5. 4. Spectral Control of Functional Fiber Sources

   Författare :Robert Lindberg; Valdas Pasiskevicius; Stefano Taccheo; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Optics and Photonics; Optik och fotonik;

   Sammanfattning : This thesis is based on five projects aimed at spectral control of fiber-based laser architectures. Two of these concern electrically wavelength-tunable laser sources, namely a fiber amplifier system for CO2-monitoring and a novel tunable laser design for flexible pulsed operation. LÄS MER

7. 5. Novel Technologies for Mode-Locking of Solid-State Lasers

   Författare :Niels Meiser; Valdas Pasiskevicius; Steinmeyer Günter; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; laser; mode-locked laser; pulsed laser; quantum dot; carbon nanotube; nonlinear optics; saturable absorber; Kerr-lens mode-locking; ultra-fast laser; picosecond laser; pulsed laser; semiconductor saturable absorber;

   Sammanfattning : The subject of this thesis is the investigation of novel technologies for mode-locking of diode-pumped, solid-state lasers. Novel saturable absorbers are used: quantum dots (QDs) and carbon nanotubes (CNTs), which both are low-dimensional nano-formations. In addition, mode-locking by cascaded nonlinearities is explored. LÄS MER