Sökning: "two-photon"

Visar resultat 1 - 5 av 116 avhandlingar innehållade ordet two-photon.

1. 1. Two-Photon Excited Fluorescence Depolarisation : Experimental and Theoretical Development

   Författare :Linus Ryderfors; Emad Mukhtar; Lennart B.-Å. Johansson; Yehudi K. Levine; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Two-photon excitation; Fluorescence; Fluorescence depolarisation; Fluorescence anisotropy; Time-correlated single photon counting; Gold nanoparticles; Rotational diffusion; Excited state symmetry; Extended Förster theory; Orientation correlation functions; Donor-donor energy migration DDEM ; Chemical physics; Kemisk fysik;

   Sammanfattning : We have studied fundamental aspects of time-resolved two-photon excited fluorescence depolarisation. The thesis presents experimental as well as theoretical progress. LÄS MER

3. 2. Study of Two-Photon processes at low Q2 using the VSAT calorimeter in the DELPHI experiment

   Författare :Pavel Tyapkin; Partikel- och kärnfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; högenergi; QCD; STIC; VSAT; DELPHI; LEP; antitag; double tag; single tag; photon structure function; hadronic cross-section; virtual photons; two-photon; gamma-gamma; Kosmisk strålning; cosmic rays; High energy interactions; PHOJET; TWOGAM; PYTHIA; VDM; GSP; Fysicumarkivet A:2004:Tyapkin;

   Sammanfattning : The study is based on data collected at the LEP II accelerator during the second period of the Large Electron-Positron collider operations (1996-2000). During that time the DELPHI (DEtector with Lepton, Photon and Hadron Identification) experiment collected about 90 Gb of data on tape corresponding to 687-691 pb-1 of luminosity. LÄS MER

4. 3. Phase Modulation Two-Photon Microscopy of Hybrid Halide Perovskite

   Författare :Qi Shi; NanoLund: Centre for Nanoscience; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Phase modulation; two-photon microscopy; perovskite; trap; carrier recombination;

   Sammanfattning : Recently, intense research activities have been focused on solution-processed hybrid lead halide perovskite semiconductors which are being developed for the solar-cell, light emitting diode (LED), and lasing applications. To optimize and fabricate a competitive perovskite-based optoelectronic device, the fundamental studies of the electronic structure, photo-generated carrier dynamics as well as the photoluminescence (PL) & photocurrent (PC) response are necessary and of great significance. LÄS MER

5. 4. Circumventing Spectrum Mismatch - Studies of Triplet-Triplet Annihilation Upconversion, Singlet Fission and Two-Photon Absorption in Photoactive Materials

   Författare :Deise Fernanda Barbosa de Mattos; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; singlet fission; solar energy conversion; two-photon absorption; energy transfer; triplet-triplet annihilation upconversion; spectroscopy.; carbon nitride quantum dots; self-assembly gels; photochemistry;

   Sammanfattning : Solar energy stands out for its potential to supply the global energy demand by itself. Therefore, it is of great value to expand the use of processes that involve light such as conversion to electricity or fuels, or to drive high-energy reactions. LÄS MER

7. 5. Two-Photon Absorption and Photorefraction in Semiconductors and Ferroelectrics

   Författare :Johan Bergquist; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Two-photon absorption spectra of Al0.4Ga0.6As/GaAs quantum wells in static electric fields are investigated experimentally. A drastic field-induced increase in the absorption peaks at energies close to half the bandgap energy is reported for the first time. LÄS MER