% 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”.

@ARTICLE{Mikulics:1010546,
      author       = {Mikulics, Martin and Adam, Roman and Chen, Genyu and
                      Chakraborty, Debamitra and Cheng, Jing and Pericolo, Anthony
                      and Komissarov, Ivan and Bürgler, Daniel E. and Heidtfeld,
                      Sarah F. and Serafini, John and Preble, Stefan and
                      Sobolewski, Roman and Schneider, Claus M. and Mayer, Joachim
                      and Hardtdegen, Hilde H.},
      title        = {{D}etermination of {T}hermal {D}amage {T}hreshold in {TH}z
                      {P}hotomixers {U}sing {R}aman {S}pectroscopy},
      journal      = {Crystals},
      volume       = {13},
      number       = {8},
      issn         = {2073-4352},
      address      = {Basel},
      publisher    = {MDPI},
      reportid     = {FZJ-2023-03120},
      pages        = {1267 -},
      year         = {2023},
      abstract     = {The increase of device lifetime and reliability of THz
                      photomixers will play an essential role in their possible
                      future application. Therefore, their optimal work
                      conditions/operation range, i.e., the maximal incident
                      optical power should be experimentally estimated. We
                      fabricated and tested THz photomixer devices based on
                      nitrogen-implanted GaAs integrated with a Bragg reflector.
                      Raman spectroscopy was applied to investigate the material
                      properties and to disclose any reversible or irreversible
                      material changes. The results indicate that degradation
                      effects in the photomixer structures/material could be
                      avoided if the total optical power density does not exceed
                      levels of about 0.7 mW/µm2 for 100 min of operation.
                      Furthermore, the investigations performed during 1000 min of
                      optical exposure on the photomixer devices’ central region
                      comprising interdigitated metal-semiconductor-metal (MSM)
                      structures suggest a reversible “curing” mechanism if
                      the power density level of ~0.58 mW/µm2 is not exceeded.
                      Long-term operation (up to 1000 h) reveals that the
                      photomixer structures can withstand an average optical power
                      density of up to ~0.4 mW/µm2 without degradation when
                      biased at 10 V. Besides the decrease of the position of the
                      A1g (LO) Raman mode from ~291 cm−1 down to ~288 cm−1
                      with increasing optical power density and operation time,
                      broad Raman modes evolve at about 210 cm−1, which can be
                      attributed to degradation effects in the active
                      photomixer/MSM area. In addition, the performed carrier
                      lifetime and photomixer experiments demonstrated that these
                      structures generated continuous wave sub-THz radiation
                      efficiently as long as their optimal work
                      conditions/operation range were within the limits
                      established by our Raman studies.},
      cin          = {ER-C-2 / PGI-6},
      ddc          = {540},
      cid          = {I:(DE-Juel1)ER-C-2-20170209 / I:(DE-Juel1)PGI-6-20110106},
      pnm          = {5353 - Understanding the Structural and Functional Behavior
                      of Solid State Systems (POF4-535)},
      pid          = {G:(DE-HGF)POF4-5353},
      typ          = {PUB:(DE-HGF)16},
      UT           = {WOS:001056274200001},
      doi          = {10.3390/cryst13081267},
      url          = {https://juser.fz-juelich.de/record/1010546},
}