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@PHDTHESIS{Hlsenbusch:619405,
      author       = {Hülsenbusch, Thomas},
      othercontributors = {Maier, Andreas and Kärtner, Franz},
      title        = {{O}ptimizing {W}hite-light {G}eneration for an {O}ptical
                      {P}arametric {C}hirped {P}ulse {A}mplifier used as a
                      {T}itanium-{S}apphire {S}eed {L}aser},
      school       = {Universität Hamburg},
      type         = {Dissertation},
      address      = {Hamburg},
      publisher    = {Verlag Deutsches Elektronen-Synchrotron DESY},
      reportid     = {PUBDB-2024-07610, DESY-THESIS-2024-019},
      series       = {DESY-THESIS},
      pages        = {181},
      year         = {2024},
      note         = {Dissertation, Universität Hamburg, 2024},
      abstract     = {Compact high-brightness electron beam sources are
                      advantageous for industrial, medicaland scientific
                      applications. Laser-plasma acceleration has the potential to
                      meet thisneed, as it can provide acceleration fields that
                      are orders of magnitude higher than inclassical linear
                      accelerators based on modern radio-frequency technology,
                      allowing formuch smaller accelerators. However, to make
                      laser-plasma acceleration competitivewith modern
                      radio-frequency linear accelerators, the quality of the
                      driving laser pulses,on which the electron beam quality
                      largely depends, needs to be improved. This thesiswas
                      carried out in the framework of LUX at the Deutsches
                      Elektronen-Synchrotron,a laser-plasma accelerator driven by
                      the 200 TW peak power titanium-sapphire lasercalled ANGUS.
                      At this facility it has been shown that the quality of the
                      generatedelectron beam depends significantly on the position
                      of the laser focus in the plasmaaccelerator and thus also on
                      the central wavelength of the drive pulse. It has also
                      beenshown that degradation and long-term effects in the
                      current ANGUS laser front-endnegatively affect the stability
                      of the accelerated electrons.This thesis presents the
                      development of a novel seed laser for
                      titanium-sapphirelaser-plasma acceleration drive lasers
                      based on white-light generation seeded opticalparametric
                      chirped pulse amplification. The focus of this work is on
                      the passive andactive stabilization of the central
                      wavelength after the parametric amplifier stage.
                      Aphase-sensitive measurement method is applied to optimize
                      the complex interactionbetween white-light generation and
                      the parametric amplifier. When this method isused to examine
                      the entire spectrum rather than just one parameter, such as
                      the centralwavelength, the characteristics of the various
                      sources of influence on the amplifiedspectrum become
                      apparent. The engineered version of the seed laser delivers
                      > 40 μJpulses at 1 kHz supporting a transform limited pulse
                      duration of 23 fs. It was shownthat the relative central
                      wavelength stability of < 2×10-4 is more than a factor of
                      2better than that of the previous front-end in ANGUS, which
                      it replaced in July 2022.With the new seed laser the central
                      wavelength stability, pulse duration and pulseduration
                      stability of the entire ANGUS drive laser was significantly
                      improved. Sincethe installation of the new seed laser, more
                      than 50 successful electron beam timeshave been performed at
                      LUX. In July 2024, another version of the same seed laser
                      wasinstalled at KALDERA, which is a laser-plasma accelerator
                      for demonstrating higherrepetition rates of up to 1 kHz.
                      With the increased repetition rate, the
                      phase-sensitivemethod can be applied there to assist in the
                      development of electron beam sourceswith improved
                      stability.},
      cin          = {MLS},
      cid          = {I:(DE-H253)MLS-20210107},
      pnm          = {621 - Accelerator Research and Development (POF4-621) /
                      PHGS, VH-GS-500 - PIER Helmholtz Graduate School
                      $(2015_IFV-VH-GS-500)$},
      pid          = {G:(DE-HGF)POF4-621 / $G:(DE-HGF)2015_IFV-VH-GS-500$},
      experiment   = {EXP:(DE-H253)LUX-Beamline-20221201},
      typ          = {PUB:(DE-HGF)3 / PUB:(DE-HGF)11},
      doi          = {10.3204/PUBDB-2024-07610},
      url          = {https://bib-pubdb1.desy.de/record/619405},
}