Sökning: "exciton binding energy"

Visar resultat 1 - 5 av 22 avhandlingar innehållade orden exciton binding energy.

  1. 1. Optical properties and degradation of deep ultraviolet AIGaN-based light-emitting diodes

    Författare :Andrea Pinos; Saulius Marcinkevicius; Andreas Hangleiter; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; AIGaN; deep-UV LEDs; polarization fields; screening; exciton binding energy; alloy fluctuations; near-field microscopy; carrier dynamics; LED aging; Optics; Optik;

    Sammanfattning : .... LÄS MER

  3. 2. Atomic Scale Modelling in Photoelectrocatalysis : Towards the Development of Efficient Materials for Solar Fuel Production

    Författare :Giane B. Damas; Carlos Moyses Araujo; Rajeev Ahuja; Clas Persson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Photocatalytic hydrogen production; polymeric materials; donor-acceptor architecture; small molecules; density functional theory; hydrogen binding free energies; exciton binding energies; electrocatalysis; carbon dioxide conversion; formic acid production; Sn-based electrodes; Tin oxides; Ru-complexes; Metal Organic Frameworks; carbon dioxide capture.;

    Sammanfattning : Using sunlight to produce valuable chemicals has been pointed out as an interesting alternative to deal with the well-known environmental problem related to the use of fossil fuels for energy generation. Thus, it is crucial for this field the development of novel photocatalysts that could drive the uphill reactions with high efficiency while presenting low price and toxicity. LÄS MER

  4. 3. Excitonic Effects and Energy Upconversion in Bulk and Nanostructured ZnO

    Författare :Shula Chen; Irina Buyanova; Weimin Chen; Detlev M. Hofmann; Linköpings universitet; []
    Nyckelord :;

    Sammanfattning : Zinc Oxide (ZnO), a II-VI wurtzite semiconductor, has been drawing enormous research interest for decades as an electronic material for numerous applications. It has a wide and direct band gap of 3.37eV and a large exciton binding energy of 60 meV that leads to intense free exciton (FX) emission at room temperature. LÄS MER

  5. 4. 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

  7. 5. Electrical and Optical Properties of AlGaAs/GaAs Aperiodic Superlattices and Resonant Tunneling Diodes. Theory, Design and Applications

    Författare :Simon Mang Cao; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; exciton-assisted transport; miniband; high-speed quantum electronics; optical properties; ultrafast optoelectronics; field-induced transport; irregular superlattices; nanometer-scale heterostructures; laser diodes; resonant tunneling;

    Sammanfattning : The objective of the work presented in this thesis is to study quantum transport and optical properties of aperiodic superlattices and resonant tunneling diodes using III-V semiconductor heterostructures grown by molecular beam epitaxy. The study follows a procedure of theoretical modeling, computer-aided design and simulation, sample growth, and measurements. LÄS MER