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Mechanical quality factor of a sapphire fiber at cryogenic temperatures

T. Uchiyama·T. Tomaru·D. Tatsumi·S. Miyoki·M. Ohashi·K. Kuroda·T. Suzuki·A. Yamamoto·T. Shintomi
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Abstract

A mechanical quality factor of $1.1 \times 10^{7}$ was obtained for the 199 Hz bending vibrational mode in a monocrystalline sapphire fiber at 6 K. Consequently, we confirm that pendulum thermal noise of cryogenic mirrors used for gravitational wave detectors can be reduced by the sapphire fiber suspension.

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T. Uchiyama, T. Tomaru, D. Tatsumi, S. Miyoki, M. Ohashi, K. Kuroda, T. Suzuki, A. Yamamoto, T. Shintomi. 2000-07-27. Mechanical quality factor of a sapphire fiber at cryogenic temperatures. https://doi.org/10.1016/s0375-9601(00)00514-4

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