Sökning: "Molecular excitons"

Visar resultat 1 - 5 av 29 avhandlingar innehållade orden Molecular excitons.

  1. 1. 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

  2. 2. Microscopic Mechanisms of the Formation, Relaxation and Recombination of Excitons in Two-Dimensional Semiconductors

    Författare :Samuel Brem; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; relaxation dynamics; 2D materials; density matrix formalism; excitons; exciton-phonon interaction; Bloch equations;

    Sammanfattning : Monolayers of Transition Metal Dichalcogenides (TMDs) present a giant leap forward towards the realization of semiconductor devices with atomic scale thickness. As a natural consequence of their two-dimensional character TMDs exhibit a reduced dielectric screening, leading to the formation of unusually stable excitons, i.e. LÄS MER

  3. 3. Resonant Interactions Between Nanoparticle Plasmons and Molecular Excitons

    Författare :Gülis Zengin; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; surface-enhanced absorption; J-aggregates; Localized surface plasmon resonance; strong coupling; Rhodamine 6G; nanoparticles;

    Sammanfattning : Molecular plasmonics involves the study and applications of plasmonic metal nanostructures interacting with molecules. It has been a basis for development of fundamental understandings of light-matter interactions as well as of new technologies, including biological and chemical sensors and plasmon-enhanced spectroscopies. LÄS MER

  4. 4. Microscopic Modeling of Exciton Propagation and Dissociation in Two-Dimensional Materials

    Författare :Raul Perea Causin; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; 2D materials; excitons; dissociation; many-particle physics; propagation; dynamics;

    Sammanfattning : Atomically thin materials have been in the spotlight of research during the last decade due to their exceptional properties, providing a platform for the study of novel physical phenomena. In particular, transition metal dichalcogenides (TMDs) have emerged as promising atomically thin materials for future optoelectronic applications owing to their strong light-matter interaction and their high tunability. LÄS MER

  5. 5. Quantum Theory of Exciton-Exciton Interactions in Atomically Thin Semiconductors

    Författare :Daniel Erkensten; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; excitons; transition-metal dichalcogenides; many-body theory; van der Waals heterostructures; 2D materials;

    Sammanfattning : Atomically thin materials such as transition-metal dichalcogenides (TMDs) have emerged as an unprecedented platform for engineering future optoelectronic devices and studying exotic quantum phases of matter. In particular, the strong Coulomb interaction in these materials enables the formation of tightly-bound excitons, electron-hole pairs with neither purely fermionic nor bosonic character. LÄS MER