Sökning: "non-linear optics"

Visar resultat 21 - 25 av 48 avhandlingar innehållade orden non-linear optics.

1. 21. Phase Modulation Techniques for On-Off Keying in Optical Fibre Transmission

   Författare :Marco Forzati; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; return-to-zero; fibre optics communication; phase modulation; nonlinear optics; dispersion management; high-speed optical transmission; modulation formats; fibres;

   Sammanfattning : Increasing the channel bit rate is an efficient way to upgrade traffic capacity in installed transmission links. At bit rates of the order of 40 Gb/s, on-off keying (OOK) transmission becomes severely impaired by non-linear effects especially Intra-channel Four-Wave Mixing (IFWM) which limit the power at which the signal can be transmitted, and ultimately the transmission distance. LÄS MER

3. 22. An Intense Attosecond Light Source - from Generation to Application

   Författare :Linnea Rading; Atomfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; High-order Harmonic Generation; Intense XUV pulses; Velocity map imaging spectrometer; Fysicumarkivet A:2017:Rading;

   Sammanfattning : Short and intense XUV pulses are important tools to study ultrafast dynamics and non-linear processes in matter. These pulses can be generated by free electron lasers (FELs) or by high-order harmonic generation (HHG), which are two complementary techniques. LÄS MER

4. 23. Calculations on the possibilities for photoionization-delay studies with circularly polarized light

   Författare :Johanna Sörngård; Eva Lindroth; Markus Kowalewski; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Attosecond physics; photoionization delay; circular polarization; Theoretical Physics; teoretisk fysik;

   Sammanfattning : Advances in experimental physics, specifically light sources emitting at an attosecond time scale, has enabled the time resolution of atomic processes like photoionization. Recent developments have allowed these sources to produce light with non-linear polarization. LÄS MER

5. 24. Formation and Dynamics of Molecular Excitons and their Fingerprints in Nonlinear Optical Spectroscopy

   Författare :Pär Kjellberg; Kemisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; supraledare; magnetisk resonans; spektroskopi; Physical chemistry; Fysikalisk kemi; Photochemistry; Fotokemi; Kondenserade materiens egenskaper:elektronstruktur; magnetiska och optiska ; egenskaper elektriska; supraconductors; magnetic resonance; relaxation; spectroscopy; Fysik; Chemistry; Kemi; Condensed matter:electronic structure; electrical; Physics; Redfield relaxation theory ; Inhomogeneous broadening ; Time-dependent density functional theory ; Conjugated polymers ; Three-pulse photon echo ; Molecular excitons ; magnetic and optical properties; Nonlinear spectroscopy ;

   Sammanfattning : An efficient transfer of energy in molecular systems has proven to be of fundamental importance both in nature and industrial applications. The ability of molecules to work together forming collective excitations, so-called excitons, plays a key role in for example the extraordinary fast energy transfer involved in the first steps of photosynthesis. LÄS MER

7. 25. Development and applications of theoretical algorithms for simulations of materials at extreme conditions

   Författare :Igor Mosyagin; Igor Abrikosov; Sergey Simak; Andrei Postnikov; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Materials at extreme conditions exhibit properties that differ substantially from ambient conditions. High pressure and high temperature expose anharmonic, non-linear behavior, and can provoke phase transitions among other effects. Experimental setups to study that sort of effects are typically costly and experiments themselves are laborious. LÄS MER