Sökning: "pulse characterisation"

Visar resultat 1 - 5 av 26 avhandlingar innehållade orden pulse characterisation.

  1. 1. Electronic materials : growth and characterisation

    Författare :Michael A. Grishin; Ulf O. Karlsson; Massimo Sancrotti; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrophysics; Photoemission; Ultra-short laser pulse; Thin film; Laser deposition; InSb; InAs; GaSb; Ferroelectrics; Elektrofysik; Electrophysics; Elektrofysik;

    Sammanfattning : In this thesis the InSb(111), InAs(111) and GaSb(001) surfaces have been studied by means of time- and angle-resolved photoemission spectroscopy based upon the femtosecond laser system. The pump-and-probe technique allows to analyse both electron states in the valence band and normally unpopulated electron states above the valence band, which can be occupied by transiently excited carriers at the optically pumped surface. LÄS MER

  3. 2. Characterisation and Applications of Ultrashort Extreme Ultraviolet Pulses

    Författare :Johan Norin; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ultrashort pulses; pulse characterisation; sidebands; interferometry; Atom- och molekylärfysik; acetylene; Atomic and molecular physics; High-order harmonics; XUV; Fysicumarkivet A:2002:Norin;

    Sammanfattning : When a strong laser field interacts with free atoms, harmonics up to very high orders are created. This extreme ultraviolet (XUV) radiation has interesting properties, such as spatial and temporal coherence, short pulse duration and high brightness. This thesis concentrates on the temporal aspects of this radiation. LÄS MER

  4. 3. Applications of Short Extreme Ultraviolet Pulses to the Spectroscopy of Atoms and Molecules

    Författare :Allan Johansson; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; High-order harmonics; short pulses; pulse characterisation; sidebands; lifetime measurements; time domain spectroscopy; frequency domain spectroscopy; He; N2; CO; XUV; Atomic and molecular physics; relative polarisation; Atom- och molekylärfysik; Fysicumarkivet A:2003:Johansson;

    Sammanfattning : This thesis is devoted to the characterisation in time and frequency, and to spectroscopic application, of extreme ultraviolet (XUV) pulses. High-order harmonic generation or wave mixing processes were used to produce the pulses in the XUV spectral region. LÄS MER

  5. 4. High-Order Harmonics- Characterisation, Optimisation and Applications

    Författare :Claire Lyngå; Atomfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; high-harmonic generation; VUV spectroscopy; high-power lasers; Atomic and molecular physics; radiative lifetimes; XUV spectroscopy; Atom- och molekylärfysik; Fysicumarkivet A:1999:Lyngå;

    Sammanfattning : Recent advances in laser technology, with the development of extremely short-pulse, high-intensity lasers, have opened doors to new areas in atomic physics. By focusing light from an intense, short-pulse laser into a gas jet, the emission of high-order harmonics of the laser frequency has been studied. LÄS MER

  7. 5. Plasma characterisation in high power pulsed magnetron sputtering

    Författare :Jones Alami; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : In this thesis, plasma parameters including plasma and floating potentials, electron energy distribution function (EEDF) plasma density and electron temperature are studied in a high power pulsed magnetron (HPPM) discharge at different Argon (Ar) gas pressures and different magnetron powers. It is reported that the EEDF during and shortly after the pulse can be represented by a bi-Maxwellian distribution indicating two energy groups of electrons. LÄS MER