Marco Wisse

Publications (19) View all

• Source

  Available from: L. Marot

  Dataset: Spectroscopic reflectometry of mirror surfaces during plasma exposure.

  M Wisse, B Eren, L Marot, R Steiner, E Meyer
• Source

  Available from: Marco Wisse

  Article: Laser damage thresholds of ITER mirror materials and first results on in situ laser cleaning of stainless steel mirrors

  M Wisse, L Marot, B Eren, R Steiner, D Mathys, E Meyer
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  ABSTRACT: A laser ablation system has been constructed and used to determine the damage threshold of stainless steel, rhodium and single-, poly-and nanocrystalline molybdenum in vacuum, at a number of wavelengths between 220 and 1064 nm using 5 ns pulses. All materials show an increase of the damage threshold with decreasing wavelength below 400 nm. Tests in a nitrogen atmosphere showed a decrease of the damage threshold by a factor of two to three. Cleaning tests have been performed in vacuum on stainless steel samples after applying mixed Al/W/C/D coatings using magnetron sputtering. In situ XPS analysis during the cleaning process as well ex situ reflectivity measurements demonstrate near complete removal of the coating and a substantial recovery of the reflectivity. The first results also show that the reflectivity obtained through cleaning at 532 nm may be further increased by additional exposure to UV light, in this case 230 nm, an effect which is attributed to the removal of tungsten dust from the surface.
  Fusion Engineering and Design 10/2012; · 1.49 Impact Factor
• Source

  Available from: Marco Wisse

  Article: Spectroscopic reflectometry of mirror surfaces during plasma exposure.

  M Wisse, B Eren, L Marot, R Steiner, E Meyer
  [show abstract] [hide abstract]
  ABSTRACT: An in situ spectroscopic reflectometry system has been built to investigate the evolution of the specular reflectivity spectrum of ITER first mirror samples during plasma exposure. Results are presented for three different types of molybdenum mirror samples that were exposed to deuterium plasma, including single crystalline, nanocrystalline, and polycrystalline molybdenum. The results show good agreement with ex situ measurements of the reflectivity spectrum before and after exposure and extend the results obtained in previous experiments.
  The Review of scientific instruments 01/2012; 83(1):013509. · 1.52 Impact Factor
• Source

  Available from: Marco Wisse

  Article: Reflective metallic coatings for first mirrors on ITER

  B. Eren, L. Marot, A. Litnovsky, M. Matveeva, R. Steiner, V. Emberger, M. Wisse, D. Mathys, G. Covarel, E. Meyer
  Fusion Engineering and Design 01/2011; 86(9-11):2593-6. · 1.49 Impact Factor
• Source

  Available from: Marco Wisse

  Article: The effect of low temperature deuterium plasma on molybdenum reflectivity

  B. Eren, L. Marot, M. Langer, R. Steiner, M. Wisse, D. Mathys, E. Meyer
  Nuclear Fusion 01/2011; 51:103025. · 4.09 Impact Factor