Sökning: "carrier dynamics"

Visar resultat 36 - 40 av 98 avhandlingar innehållade orden carrier dynamics.

  1. 36. Time-Resolved Photoemission Electron Microscopy: Development and Applications

    Författare :Lukas Wittenbecher; NanoLund: Centre for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PEEM; time-resolved PEEM; ultrafast optics; pulse shaping; plasmonics; semiconductor nanowires; hot electrons; ultrafast microscopy; charge carrier relaxation;

    Sammanfattning : Time-resolved photoemission electron microscopy (TR-PEEM) belongs to a class of experimental techniquescombining the spatial resolution of electron-based microscopy with the time resolution of ultrafast opticalspectroscopy. This combination provides insight into fundamental processes on the nanometer spatial andfemto/picosecond time scale, such as charge carrier transport in semiconductors or collective excitations ofconduction band electrons at metal surfaces. LÄS MER

  3. 37. Protein Folding and DNA Origami

    Författare :Mark Marvin Seibert; David van der Spoel; Helmut Grubmüller; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; protein folding; Molecular Dynamics simulations; DNA origami; Biophysics; Biofysik; Physics with specialization in Biophysics; Fysik med inriktning mot biofysik;

    Sammanfattning : In this thesis, the folding process of the de novo designed polypeptide chignolin was elucidated through atomic-scale Molecular Dynamics (MD) computer simulations. In a series of long timescale and replica exchange MD simulations, chignolin’s folding and unfolding was observed numerous times and the native state was identified from the computed Gibbs free-energy landscape. LÄS MER

  4. 38. Phase Modulation Two-Photon Microscopy of Hybrid Halide Perovskite

    Författare :Qi Shi; NanoLund: Centre for Nanoscience; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Phase modulation; two-photon microscopy; perovskite; trap; carrier recombination;

    Sammanfattning : Recently, intense research activities have been focused on solution-processed hybrid lead halide perovskite semiconductors which are being developed for the solar-cell, light emitting diode (LED), and lasing applications. To optimize and fabricate a competitive perovskite-based optoelectronic device, the fundamental studies of the electronic structure, photo-generated carrier dynamics as well as the photoluminescence (PL) & photocurrent (PC) response are necessary and of great significance. LÄS MER

  5. 39. At the heart of Quantum Materials: Magnetism as a means and an end from a muon perspective

    Författare :Konstantinos Papadopoulos; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetism; ion dynamics; phase transitions; muon spectroscopy; correlated systems; quantum materials;

    Sammanfattning : Functional materials are at the center of solid state physics research and technological innovation in our era. In order to create (semi)autonomous, high precision and lightning-fast devices it is necessary to explore, modify and control the intrinsic properties of matter. LÄS MER

  7. 40. Time-resolved optical characterisation of defect-rich semiconductors

    Författare :Andreas Gaarder; KTH; []
    Nyckelord :;

    Sammanfattning : This thesis explores carrier trapping and recombination indefect-rich semiconductors, and methods for materialcharacterisation. Optimal manufacturing parameters areestablished for materials to be used in the ultrafast devicesneeded for future telecommunication applications. LÄS MER