Field dependent surface resistance of niobium on copper cavities

  title={Field dependent surface resistance of niobium on copper cavities},
  author={Tobias Junginger},
  journal={Physical Review Special Topics-accelerators and Beams},
  • T. Junginger
  • Published 2 December 2014
  • Materials Science, Physics
  • Physical Review Special Topics-accelerators and Beams
The surface resistance ${R}_{\mathrm{S}}$ of superconducting cavities prepared by sputter coating a niobium film on a copper substrate increases significantly stronger with the applied rf field compared to cavities of bulk material. A possible cause is that the thermal boundary resistance between the copper substrate and the niobium film induces heating of the inner cavity wall, resulting in a higher ${R}_{\mathrm{S}}$. Introducing helium gas in the cavity, and measuring its pressure as a… 

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