Sökning: "Molecular excitons"

Visar resultat 6 - 10 av 29 avhandlingar innehållade orden Molecular excitons.

  1. 6. Moiré Exciton Landscape and its Optical Properties in Two-Dimensional Semiconductors

    Författare :Joakim Hagel; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; moiré physics; excitons; 2D materials;

    Sammanfattning : In recent years the emergence of atomically thin nanomaterials has led to a new research venue, revealing intriguing properties making them an excellent platform to study many-particle quantum phenomena. Of particular interest is the class of nanomaterials called transition metal dichalcogenides (TMDs), where the strong light-matter coupling reveals promising opportunities in the pursuit of novel optoelectronical devices. LÄS MER

  3. 7. Optical properties of point defects in insulators and of transition metal dichalcogenides

    Författare :Christopher Linderälv; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; luminescence quenching; charge transition levels; excitons; transition metal dichalcogenides; monolayer alloys; solid state lighting; color centers; oxygen vacancies; moiré structures; wide band gap oxides;

    Sammanfattning : There is a need for new or modified materials, both to improve current devices and to create novel functionalities. Engineering materials to target specific functionalities requires a better understanding of how microscopic processes impact materials properties. LÄS MER

  4. 8. Electronic and Vibrational Coherence in Photosynthetic and Model Systems

    Författare :Mirianas Chachisvilis; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Kemi; Chemistry; Ultrafast relaxation; Porphyrins; Delocalization; Anisotropy; Wavepacket; Vibrational Coherence; Excitons; Electronic coherence; Energy transfer; Femtosecond spectroscopy; Photosynthesis;

    Sammanfattning : Ultrafast optical response and excitation energy dynamics in light harvesting pigment-protein complexes and in a few model systems have been studied both experimentally and theoretically. Femtosecond light pulses were employed to excite the system and monitor the subsequent time evolution of the transient absorption kinetics and anisotropy. LÄS MER

  5. 9. Life of Excitons in Artificial Photosynthetic Antennas

    Författare :Johan Andersson; Kemisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Zn-porphyrin; Osmium; Ruthenium; Polypyridine; Inter Ligand Energy Transfer; Inter System Crossing; Excited state dynamics; Transition metal complexes; Photosynthetic Antennas; Solar energy conversion; Artificial photosynthesis; Physical chemistry; Fysikalisk kemi; Transient Absorption Anisotropy.; Reaction Center; Dendrimer; Energy Transfer;

    Sammanfattning : Due to the predicted energy crisis when fossil fuels will be exhausted it is important to search for alternative energy sources. Utilizing sunlight via artificial photosynthesis is an interesting possibility. LÄS MER

  7. 10. Microscopic Theory of Externally Tunable Exciton Signatures of Two-Dimensional Materials

    Författare :Maja Feierabend; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; localized states; density matrix formalism; magnetic field; transition metal dichalcogenides; Bloch equations; organic inorganic heterostructures; dark excitons; strain;

    Sammanfattning : Atomically thin transition metal dichalcogenides (TMDs) are in the focus of current research due to their efficient light-matter interaction and the remarkably strong Coulomb interaction that leads to tightly bound excitons. Due to their unique band structure, TMDs show a variety of bright and optically inaccessible dark excitonic states. LÄS MER