Sökning: "excitons"

Visar resultat 6 - 10 av 67 avhandlingar innehållade ordet excitons.

  1. 6. Bose-Einstein Condensation of Magnetic Excitons in Semiconductor Quantum Wells

    Författare :Vitalie Boţan; Lars Nordström; Sveatoslav Moskalenko; Pavlos Lagoudakis; Uppsala universitet; []
    Nyckelord :Physics; Bose-Einstein condensation; magnetic excitons; electron-hole pairs; electron-hole liquid; magnetorotons; magnetoplasmons; superfluidity; Fysik;

    Sammanfattning : In this thesis regimes of quantum degeneracy of electrons and holes in semiconductor quantum wells in a strong magnetic field are studied theoretically. The coherent pairing of electrons and holes results in the formation of Bose-Einstein condensate of magnetic excitons in a single-particle state with wave vector K. LÄS MER

  3. 7. 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

  4. 8. 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

  5. 9. Exciton-plasmon interactions in metal-semiconductor nanostructures

    Författare :Staffan Hellström; Ying Fu; Mikael Käll; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; plasmons; excitons; quantum dots; nanoparticles; FDTD; surface plasmon polaritons; QDIP; quantum dot infrared photodetector; polaritons;

    Sammanfattning : Semiconductor quantum dots and metal nanoparticles feature very strong light-matter interactions, which has led to their use in many photonic applications such as photodetectors, biosensors, components for telecommunications etc.Under illumination both structures exhibit collective electron-photon resonances, described in the frameworks of quasiparticles as exciton-polaritons for semiconductors and surface plasmon-polaritons for metals. LÄS MER

  7. 10. Bound excitons in silicon carbide

    Författare :Tryggvi Egilsson; Gordon Davies; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The investigation of silicon carbide (SiC) is strongly motivated by the potential of this material for various demanding electronic applications. The main virtue of SiC is its toughness compared to other more common semiconductors. LÄS MER