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Damage and erosion at ceramic Windows due to high-power millimeter waves

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Abstract

The damage that occurs at alumina windows of high-power millimeter wave gyrotrons operating in TE0,n mode is investigated. This damage appears only on the air side of the window where it yields small spot-like features (diameter <1 mm) and circular "melting" patterns (diameter >1 cm). The damage observed is thought to be related to rf field enhancements by resonances of trapped electromagnetic modes and by protrusions and contaminations of the ceramic surface.

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Authors and Affiliations

  1. Institut für Höchstfrequenztechnik und Elektronik, Universität Karlsruhe, D-76128, Karlsrube, Germany

    Hans-Ulrich Nickel

  2. Institut für Materialforschung I, Kernforschungszentrum Karlsrube, D-76021, Karlsruhe, Germany

    Jürgen Halbritter

Authors
  1. Hans-Ulrich Nickel
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  2. Jürgen Halbritter
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Nickel, HU., Halbritter, J. Damage and erosion at ceramic Windows due to high-power millimeter waves. Int J Infrared Milli Waves 15, 651–664 (1994). https://doi.org/10.1007/BF02096481

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  • DOI: https://doi.org/10.1007/BF02096481

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