% 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{Baus:349000,
      author       = {Baus, Patrick},
      title        = {{C}urrent {D}rivers and {C}ontrol {E}lectronics for the
                      {L}aser {S}pectroscopy of {H}ighly {C}harged {I}ons},
      school       = {Technische Universität Darmstadt},
      type         = {Dissertation},
      address      = {Darmstadt},
      publisher    = {ULB Darmstadt},
      reportid     = {GSI-2024-00461},
      pages        = {239 Seiten},
      year         = {2024},
      note         = {Dissertation, Technische Universität Darmstadt, 2023},
      abstract     = {Recent years have seen an ever increasing range of laser
                      diodes covering the spectral range from ultraviolet to
                      infrared. The classic 780 nm and 830 nm NIR laser diodes
                      have been well established and many laser designs were
                      developed with design parameters for such diodes. Over the
                      years the disparity in development efforts between laser
                      diodes and supporting electronic systems has led to a subpar
                      performance of such systems compared to NIR diode lasers.
                      The desire for high resolution spectroscopy of highly
                      charged ions having optically accessible transitions in the
                      ultraviolet and blue regime sparked an interest in high
                      precision and compact diode lasers systems addressing these
                      needs. At the same time, other applications like quantum
                      computing, using arrays of neutral atoms, have seen an
                      increasing demand for customized, compact diode laser
                      systems for the addressing and coherent manipulation of
                      hundreds of individual quantum systems on the way to even
                      larger systems scaling to thousands of qubits. All of these
                      use cases require state of the art diode laser systems
                      designed for modern laser diodes with unprecedented
                      stability and noise performance surpassing many of the
                      solutions currently available. This work compares several
                      commercial products and devices developed in academia used
                      as building blocks for diode laser system like laser drivers
                      and temperature controllers. The laser current driver
                      performance is tested in terms of compliance voltage, output
                      noise, stability with respect to both temperature and time
                      and their output impedance, which is a measure for their
                      noise suppression capability. The limitations found with the
                      tested devices are identified and their causes are explained
                      analytically and with simulations. The laser temperature
                      controllers which are inherently closed-loop instruments
                      whose performance is determined by their front end were
                      tested in terms of noise and stability using reference
                      resistors against a reference thermometer. These results led
                      to the development of a novel fully digital laser diode
                      driver and temperature controller surpassing other solutions
                      in terms of performance by at least one order of magnitude
                      while being open-source and highly customisable to allow
                      adapting to the needs of both high-resolution spectroscopy
                      and coherent control of quantum systems. The laser current
                      driver implements a unique architecture that isolates the
                      current source from the load to combine the high compliance
                      voltage, demanded by modern high performance laser diode,
                      with ultra-low current noise and stability, providing
                      sub-shot noise performance between 20 mA and 500 mA,
                      delivering a performance close to the limits allowed by
                      physics. This is combined with an outstanding noise immunity
                      allowing the use of compact switch-mode supplies to power
                      those laser drivers without impacting their performance. The
                      digital temperature controller, again an open-source design,
                      provides definitive sub-mK performance with µK resolution.
                      The stability of this system is defined by the performance
                      of the thermistor used, shifting the focus towards the
                      mechanical resonator design as the ultimate performance
                      limit. Finally, a data logging system is presented that
                      accompanies these high precision instruments to monitor the
                      environment of the laboratory, the experiment and instrument
                      parameters to give the experimenter real-time information on
                      the state of the systems along with user-definable alerts to
                      protect those assets. All of these developments are in
                      extensive use at several state of the art experiments and
                      are considered essential for their progress.},
      cin          = {ATP},
      cid          = {I:(DE-Ds200)ATP-20051214OR020},
      pnm          = {631 - Matter – Dynamics, Mechanisms and Control
                      (POF4-631)},
      pid          = {G:(DE-HGF)POF4-631},
      experiment   = {$EXP:(DE-Ds200)no_experiment-20200803$},
      typ          = {PUB:(DE-HGF)11},
      urn          = {urn:nbn:de:tuda-tuprints-276077},
      doi          = {10.26083/TUPRINTS-00027607},
      url          = {https://repository.gsi.de/record/349000},
}