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arXiv · 1201.5386

Low temperature laser scanning microscopy of a superconducting radio-frequency cavity

G. Ciovati·Steven M. Anlage·C. Baldwin·G. Cheng·R. Flood·K. Jordan·P. Kneisel·M. Morrone·G. Nemes·L. Turlington·H. Wang·K. Wilson·S. Zhang
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Abstract

An apparatus was developed to obtain, for the first time, 2D maps of the surface resistance of the inner surface of an operating superconducting radio-frequency niobium cavity by a low-temperature laser scanning microscopy technique. This allows identifying non-uniformities of the surface resistance with a spatial resolution of about one order of magnitude better than with earlier methods and surface resistance resolution of ~ 1 micro-Ohm at 3.3 GHz. A signal-to-noise ratio of about 10 dB was obtained with 240 mW laser power and 1 Hz modulation frequency. The various components of the apparatus, the experimental procedure and results are discussed in detail in this contribution.

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G. Ciovati, Steven M. Anlage, C. Baldwin, G. Cheng, R. Flood, K. Jordan, P. Kneisel, M. Morrone, G. Nemes, L. Turlington, H. Wang, K. Wilson, S. Zhang. 2012-01-25. Low temperature laser scanning microscopy of a superconducting radio-frequency cavity. https://doi.org/10.1063/1.3694570

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