Search for dissertations about: "Photon upconversion"

Showing result 1 - 5 of 13 swedish dissertations containing the words Photon upconversion.

  1. 1. Photon Upconversion in Heavily Doped Semiconductors

    Author : Kilian Mergenthaler; Fasta tillståndets fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; TEKNIK OCH TEKNOLOGIER; NATURAL SCIENCES; ENGINEERING AND TECHNOLOGY; III-V semiconductor materials; nanowires; photoluminescence; Photon upconversion; semiconductors; doping; Fysicumarkivet A:2016:Mergenthaler;

    Abstract : In this thesis the luminescence properties of highly doped semiconductors are studied with focus on degenerately n-doped InP. It is demonstrated how photoluminescence measurements on degenerately doped semiconductors allow an estimation of the doping concentration without need for electrical contacts. READ MORE

  2. 2. Advancing Upconversion Emissions for Biomedical Imaging

    Author : Haichun Liu; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; upconverting nanoparticles; luminescence; fluorescence; inverse problem; biomedical optics; biomedical imaging; photon migration; upconversion; tomography; saturation; Fysicumarkivet A:2014:Liu;

    Abstract : During the past decade, upconverting nanoparticles (UCNPs) doped with rare earth ions have become an important class of fluorescence contrast agents for molecular imaging, due to their unique properties. Their property of anti-Stokes luminescence, with both the excitation and emission wavelengths close to the optimal for biomedical imaging, has been extensively explored in various biomedical applications. READ MORE

  3. 3. Photon Upconversion through Triplet-Triplet Annihilation: Towards Higher Efficiency and Solid State Applications

    Author : Damir Dzebo; Chalmers University of Technology; []
    Keywords : solar energy conversion; triplet-triplet annihilation; energy transfer; fluorescence anisotropy; anti-stokes; photon upconversion; excited state; porphyrins; photochemistry; photophysics; delayed fluorescence; dendrimers; anthracene; oligomers; spectroscopy;

    Abstract : The sun is the only renewable energy source that can accommodate humanity’s energyneeds today and in the foreseeable future. The sunlight reaching the planet’s surfaceis filtrated through the atmosphere, reducing its UV-light intensity in the 300-400 nmrange, which indeed can be harmful to life as we know it in too large doses. READ MORE

  4. 4. Synthesis and Photophysical Characterization of Annihilator-Sensitizer Pairs for Triplet-Triplet Annihilation Based Photon Upconversion

    Author : Victor Gray; Chalmers University of Technology; []
    Keywords : NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; NATURAL SCIENCES; Triplet-Triplet Annihilation; Photon Upconversion; Anthracene;

    Abstract : Transitioning to a future society, independent of fossil fuels, will denitely require the use of solar radiation for power and fuel production. Due to energy mismatch betweendevice absorption and the broad band irradiation provided by the sun there are severe limitations to how efficient devices for direct conversion of solar radiation can be. READ MORE

  5. 5. Non-Coherent Photon Upconversion on Dye-Sensitized Nanostructured ZrO2 Films for Efficient Solar Light Harvesting

    Author : Jonas Sandby Lissau; Ana Morandeira; James M. Gardner; Leif Hammarström; Josef Michl; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; photon upconversion; triplet-triplet annihilation; DSSC; dye-sensitized; delayed fluorescence; photophysics; solar energy conversion; nanostructured surface; energy migration; Kemi med inriktning mot kemisk fysik; Chemistry with specialization in Chemical Physics;

    Abstract : Photon upconversion by sensitized triplet–triplet annihilation (UC-STTA) is a photophysical process that facilitates the conversion of two low-energy photons into a single high-energy photon. A low-energy photon is absorbed by a sensitizer molecule that produces a triplet excited state which is transferred to an emitter molecule. READ MORE