% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@PHDTHESIS{Zapolnova:449776,
      author       = {Zapolnova, Ekaterina},
      othercontributors = {Ploenjes-Palm, Elke},
      title        = {{P}ump-probe experiments, driven by high-field {TH}z
                      pulses, shaped by double electron bunches at {FLASH}},
      school       = {Universität Hamburg},
      type         = {Dissertation},
      address      = {Hamburg},
      publisher    = {Verlag Deutsches Elektronen-Synchrotron},
      reportid     = {PUBDB-2020-04003, DESY-THESIS-2020-025},
      series       = {DESY-THESIS},
      pages        = {123},
      year         = {2020},
      note         = {Dissertation, Universität Hamburg, 2020},
      abstract     = {The Free Electron Laser in Hamburg (FLASH) has a unique
                      combination of high repetitionrate, tunable, intense, and
                      narrowband THz pulses naturally synchronized to the XUV
                      pulses.It provides the opportunity to investigate
                      light-matter interaction on an ultrafast timescale.However,
                      due to the different properties of THz and XUV radiation,
                      the optical transport differsfor these pulses. The result is
                      that the optical path of the THz beamline is several meters
                      longerthan the XUV beamline, preventing the utilization of
                      the full potential of FLASH. This work demonstrates a new
                      approach for XUV-THz pump-probe experiments at
                      FELs,providing a solution to the optical path difference
                      problem of naturally synchronized THz andXUV pulses. The
                      described THz Doubler scheme is based on the generation of
                      two consecutiveelectron bunches, separated in time, to
                      enable temporal overlap of THz and XUV pulses at
                      theexperiment. The first bunch is specifically tuned for the
                      generation of THz radiation and thesecond for XUV with the
                      achieved synchronization of 19 fs r.m.s.. This new scheme
                      enablespump-probe experiments with high temporal resolution,
                      high pulse energies, and tunable XUVand THz
                      wavelengths.Temporal and spatial overlap is critical for
                      ultrafast XUV-THz pump-probe experiments, bothat FEL
                      facilities and at table-top high harmonic sources. A simple
                      and robust spatio-temporaloverlap tool was developed and is
                      presented here. It is based on ultrafast changes of the
                      opticalproperties of silicon induced by ultrafast XUV pulses
                      and probed by THz pulses, and enables thearrival time
                      between XUV and THz pulses to be measured with temporal
                      resolution comparableto the duration of the THz pulse.
                      Finally, a novel Fourier transform infrared (FTIR)
                      spectrometer, based on the reflectivelamellar grating and
                      operating over an extremely broad spectral range of THz
                      frequencies,has been developed and commissioned. The
                      lamellar grating interferometer, in contrast to thetypical
                      Michelson interferometer, has a much higher throughput and
                      almost constant frequencyresponse, making it an ideal tool
                      for spectral characterization of broadband sources.},
      cin          = {FS-FLASH-B},
      cid          = {I:(DE-H253)FS-FLASH-B-20160930},
      pnm          = {6211 - Extreme States of Matter: From Cold Ions to Hot
                      Plasmas (POF3-621) / 6G2 - FLASH (POF3-622) / PHGS,
                      VH-GS-500 - PIER Helmholtz Graduate School
                      $(2015_IFV-VH-GS-500)$},
      pid          = {G:(DE-HGF)POF3-6211 / G:(DE-HGF)POF3-6G2 /
                      $G:(DE-HGF)2015_IFV-VH-GS-500$},
      experiment   = {EXP:(DE-H253)F-ThzBL-20150101},
      typ          = {PUB:(DE-HGF)3 / PUB:(DE-HGF)11},
      doi          = {10.3204/PUBDB-2020-04003},
      url          = {https://bib-pubdb1.desy.de/record/449776},
}