Sökning: "free electron laser"

Visar resultat 1 - 5 av 94 avhandlingar innehållade orden free electron laser.

  1. 1. Studies on high brightness electron beams for short pulses and free electron laser

    Författare :Sara Thorin; Lunds universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; bunch compression; sub-ps pulses; X-rays; High brightness electron beam; free electron laser; electron accelerator; collective effects.;

    Sammanfattning : Accelerator based lightsources are one of the most powerful tools today for producing high intensity radiation at very short wavelengths. While synchrotron storage rings provide a high average brilliance in a wide wavelength range, the next generation of lightsources aim towards producing ultra-short pulses in the X-ray regime. LÄS MER

  3. 2. Efficiency Enhancement Techniques for Free-Electron Lasers

    Författare :Alan Mak; Lunds universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; free-electron laser; accelerator physics; efficiency enhancement; undulator tapering; phase jump method; synchrotron radiation; Fysicumarkivet:2017:Mak;

    Sammanfattning : The central question addressed in this thesis is how to make the free-electron laser (FEL) more efficient. In recent years, coherent diffraction imaging provides an important motivation for efficiency enhancement. This is because a more efficient FEL process enables converting a larger fraction of the electron beam's power into optical power. LÄS MER

  4. 3. Applications of time-dependent configuration-interaction singles for photoelectrons in attosecond and free-electron laser sciences

    Författare :Mattias Bertolino; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; laser-assisted photoionization; photoelectron interferometry; attosecond physics; free-electron laser; second quantization; time-dependent configuration-interaction singles; surface-flux techniques;

    Sammanfattning : This thesis addresses the theoretical treatment of photoelectrons in attosecond and free-electron laser sciences. Wehave implemented methods that extract information on the photoionization process, which we use to investigateinterferometric schemes with particular focus on multiphoton ionization and strong-field effects in attosecondmetrology and coherent control of photoelectrons in free-electron laser science. LÄS MER

  5. 4. Probing and improving coherence in Free-electron lasers

    Författare :Mihai Pop; Synkrotronljusfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Accelerators; Free electron laser; Synchrotron radiation; Coherence; Young double-slit; spectrum analysis; Simulations;

    Sammanfattning : Free electron lasers or FELs, have transformed the way science has been done in the last decades by providing coherent, highly brilliant radiation at wavelengths not achievable with conventional lasers. Their most important characteristic, along side brightness, is their coherence, which allows users to perform experiments that rely on precise phase characteristics of the probing radiation. LÄS MER

  7. 5. Zone Plates for Hard X-Ray Free-Electron Lasers

    Författare :Daniel Nilsson; Ulrich Vogt; Thomas Tschentscher; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; X-ray optics; Zone plates; XFEL; x-rays; free-electron laser; heat transfer;

    Sammanfattning : Hard x-ray free-electron lasers are novel sources of coherent x-rays with unprecedented brightness and very short pulses. The radiation from these sources enables a wide range of new experiments that were not possible with previous x-ray sources. Many of these experiments require the possibility to focus the intense x-ray beam onto small samples. LÄS MER