Search for dissertations about: "femtosecond laser thesis"

Showing result 1 - 5 of 92 swedish dissertations containing the words femtosecond laser thesis.

2. 1. Nonlinear optical techniques for ultrafast laser diagnostics : Development of femtosecond LIF, LIGS, CARS and backward lasing

   Author : Maria Ruchkina; Förbränningsfysik; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; laser diagnostics; femtosecond laser; nonlinear interactions; ultrafast spectroscopy; multi-photon excitation; laser-induced fluorescence; rotational coherent anti-Stokes Raman spectroscopy; laser-induced grating spectroscopy; lasing; backward lasing technique; Fysicumarkivet A:2021:Ruchkina;

   Abstract : The thesis work concerns development and application of four versatile nonlinear optical techniques, based on exploiting ultrashort laser pulses, for diagnostic purposes in gases and flames. The four techniques, all laser-based, are two-photon laser-induced fluorescence (TPLIF), hybrid femtosecond/nanosecond (fs/ns) rotational coherent anti-Stokes Raman scattering (fs/ns RCARS), fs-laser-induced grating spectroscopy (fs-LIGS), and backward lasing. READ MORE

4. 2. Femtosecond Laser Microfabrication of Glasses and 2D Materials for Photonics and Energy Storage

   Author : Po-Han Huang; Frank Niklaus; Göran Stemme; Kristinn Gylfason; Yves Bellouard; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Femtosecond laser; 3D printing; self-organized nanogratings; micromachining; silica glass; silicon-rich glass; hydrogen silsesquioxane; photonic microdevice; microsupercapacitor; 2D materials; direct ink writing; Electrical Engineering; Elektro- och systemteknik;

   Abstract : Femtosecond laser-based fabrication technologies have seen rapid developments in the past decades, thanks to the capability of femtosecond lasers to induce localized multiphoton absorption in materials. Multiphoton absorption can result in various material modifications that can be leveraged for additive and subtractive manufacturing. READ MORE

5. 3. Ultra-intense laser-plasma interaction for applied and fundamental physics

   Author : Arkady Gonoskov; Mattias Marklund; Gert Brodin; Vladimir Tikhonchuk; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; ultra-intense laser; femtosecond pulse; plasma; relativistic phenomena; laser-driven acceleration; attosecond pulse generation; radiation reaction; fysik; Physics;

   Abstract : Rapid progress in ultra-intense laser technology has resulted in intensity levels surpassing 1022 W/cm2, reaching the highest possible density of electromagnetic energy amongst all controlled sources available in the laboratory. During recent decades, fast growth in available intensity has stimulated numerous studies based on the use of high intensity lasers as a unique tool for the initiation of nonlinear behavior in various basic systems: first molecules and atoms, then plasma resulting from the ionization of gases and solids, and, finally, pure vacuum. READ MORE

6. 4. Ionization of large molecules with short laser pulses

   Author : Mikael Kjellberg; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fysik; Photoelectron spectroscopy; Momentum mapping imaging; thermal ionization; above threshold ionization; molecular fusion; fullerenes; polyaromatic hydrocarbons; femtosecond-laser.;

   Abstract : The decay dynamics of fullerenes and polyaromatic hydrocarbons (PAH) after femtosecond-laser excitation have been studied experimentally by electron momentum mapping and mass spectrometry. The electron spectra of fullerenes and large PAH-molecules were found to be exponentially decreasing with energy without any distinct peaks outside the photon energy. READ MORE

7. 5. Development and Applications of a Laser-Wakefield X-ray Source (updated)

   Author : Isabel Gallardo Gonzalez; Atomfysik; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; laser-wakefield acceleration; betatron radiation; ionization-induced trapping; direct laser acceleration; laser-wakefield merging; warm dense matter; phase-contract imaging;

   Abstract : In laser-wakefield acceleration (LWFA), a femtosecond laser pulse is tightly focused in a gas to intensities exceeding 1018 W/cm2 . The laser radiation ionizes the medium and excites a plasma wave that travels behind the laser pulse. READ MORE