@inproceedings{SchoppNachtrodtHeuermannetal.2012,
  author    = {Schopp, Christoph and Nachtrodt, Frederik and Heuermann, Holger and Scherer, Ulrich W. and Mostacci, Domiziano and Finger, Torsten and Tietsch, Wolfgang},
  title     = {A novel 2.45 GHz/200 W Microwave Plasma Jet for High Temperature Applications above 3600 K},
  series = {Journal of Physics : Conference Series},
  volume    = {406},
  booktitle = {Journal of Physics : Conference Series},
  number    = {012029},
  issn      = {1742-6596},
  pages     = {5},
  year      = {2012},
  language  = {en}
}
@inproceedings{OegunKlingHeuermannetal.2014,
  author    = {{\"O}gun, Celal Mohan and Kling, Rainer and Heuermann, Holger and Gr{\"a}ser, Ulrich and Schopp, Christoph},
  title     = {Elektrodenlose quecksilberfreie Niederdrucklampen betrieben mit Mikrowellen},
  series = {Licht 2014 [Elektronische Ressource] : Den Haag, Holland ; 21. Gemeinschaftstagung, 21. bis 24. September 2014 ; Tagungsband},
  booktitle = {Licht 2014 [Elektronische Ressource] : Den Haag, Holland ; 21. Gemeinschaftstagung, 21. bis 24. September 2014 ; Tagungsband},
  publisher = {Nederlandse Stichting voor Verlichtingskunde},
  address   = {Ede},
  pages     = {[Elektronische Ressource]},
  year      = {2014},
  language  = {de}
}
@inproceedings{SchoppHeuermann2013,
  author    = {Schopp, Christoph and Heuermann, Holger},
  title     = {Electrodeless low pressure lamp with bi-static matching at 2.45 GHz},
  series = {2013 European Microwave Conference (EuMC) , Nuremberg},
  booktitle = {2013 European Microwave Conference (EuMC) , Nuremberg},
  publisher = {IEEE},
  address   = {Piscataway, NJ},
  isbn      = {978-1-4799-0264-4},
  pages     = {881 -- 884},
  year      = {2013},
  language  = {en}
}
@inproceedings{SchoppHeuermannHoltrup2014,
  author    = {Schopp, Christoph and Heuermann, Holger and Holtrup, S.},
  title     = {Investigation on efficacy optimization of RF-driven automotive D-lamps},
  series = {44th European Microwave Conference (EuMC),2014, Rome},
  booktitle = {44th European Microwave Conference (EuMC),2014, Rome},
  doi       = {10.1109/EuMC.2014.6986645},
  pages     = {1154 -- 1157},
  year      = {2014},
  language  = {en}
}
@article{SchoppDollGraeseretal.2016,
  author    = {Schopp, Christoph and Doll, Timo and Gr{\"a}ser, Ulrich and Harzheim, Thomas and Heuermann, Holger and Kling, Rainer and Marso, Michael},
  title     = {Capacitively Coupled High-Pressure Lamp Using Coaxial Line Networks},
  series = {IEEE Transactions on Microwave Theory and Techniques},
  volume    = {64},
  journal   = {IEEE Transactions on Microwave Theory and Techniques},
  number    = {10},
  publisher = {IEEE},
  address   = {New York, NY},
  issn      = {0018-9480},
  doi       = {10.1109/TMTT.2016.2600326},
  pages     = {3363 -- 3368},
  year      = {2016},
  abstract  = {This paper describes the development of a capacitively coupled high-pressure lamp with input power between 20 and 43 W at 2.45 GHz, using a coaxial line network. Compared with other electrodeless lamp systems, no cavity has to be used and a reduction in the input power is achieved. Therefore, this lamp is an alternative to the halogen incandescent lamp for domestic lighting. To serve the demands of domestic lighting, the filling of the lamp is optimized over all other resulting requirements, such as high efficacy at low induced powers and fast startups. A workflow to develop RF-driven plasma applications is presented, which makes use of the hot S-parameter technique. Descriptions of the fitting process inside a circuit and FEM simulator are given. Results of the combined ignition and operation network from simulations and measurements are compared. An initial prototype is built and measurements of the lamp's lighting properties are presented along with an investigation of the efficacy optimizations using large signal amplitude modulation. With this lamp, an efficacy of 135 lmW -1 is achieved.},
  language  = {en}
}
@inproceedings{SchoppHeuermannMarso2017,
  author    = {Schopp, Christoph and Heuermann, Holger and Marso, Michel},
  title     = {Multiphysical Study of an Atmospheric Microwave Argon Plasma Jet},
  series = {IEEE Transactions on Plasma Science},
  volume    = {45},
  booktitle = {IEEE Transactions on Plasma Science},
  number    = {6},
  publisher = {IEEE},
  issn      = {1939-9375},
  doi       = {10.1109/TPS.2017.2692735},
  pages     = {932 -- 937},
  year      = {2017},
  language  = {en}
}
@article{SchoppBritunVoracetal.2019,
  author    = {Schopp, Christoph and Britun, Nikolay and Vorac, Jan and Synek, Petr and Snyders, Rony and Heuermann, Holger},
  title     = {Thermal and Optical Study on the Frequency Dependence of an Atmospheric Microwave Argon Plasma Jet},
  series = {IEEE Transactions on Plasma Science},
  volume    = {47},
  journal   = {IEEE Transactions on Plasma Science},
  number    = {7},
  publisher = {IEEE},
  address   = {New York},
  issn      = {1939-9375},
  pages     = {3176 -- 3181},
  year      = {2019},
  language  = {en}
}
@article{SchoppRohrbachLangeretal.2024,
  author    = {Schopp, Christoph and Rohrbach, Felix and Langer, Luc and Heuermann, Holger},
  title     = {Detection of welding wire length by active S11 measurement},
  series = {IEEE Transactions on Plasma Science},
  journal   = {IEEE Transactions on Plasma Science},
  number    = {Early Access},
  publisher = {IEEE},
  issn      = {0093-3813 (Print)},
  doi       = {10.1109/TPS.2024.3356659},
  pages     = {1 -- 6},
  year      = {2024},
  abstract  = {A novel method to determine the extruded length of a metallic wire for a directed energy deposition (DED) process using a microwave (MW) plasma jet with a straight-through wire feed is presented. The method is based on the relative comparison of the measured frequency response obtained by the large-signal scattering parameter (Hot-S) technique. In the practical working range, repeatability of less than 6\% for a nonactive plasma and 9\% for the active plasma state is found. Measurements are conducted with a focus on a simple solution to decrease the processing time and reduce the integration time of the process into the existing hardware. It is shown that monitoring a single frequency for magnitude and phase changes is sufficient to achieve good accuracy. A combination of different measurement values to determine the length is possible. The applicability to different diameter of the same material is shown as well as a contact detection of the wire and metallic substrate.},
  language  = {en}
}