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arXiv · 1501.06371

Material loss angles from direct measurements of broadband thermal noise

Maria Principe·Innocenzo M. Pinto·Vincenzo Pierro·Riccardo DeSalvo·Ilaria Taurasi·Akira E. Villar·Eric D. Black·Kenneth G. Libbrecht·Christophe Michel·Nazario Morgado·Laurent Pinard
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Abstract

We estimate the loss angles of the materials currently used in the highly reflective test-mass coatings of interferometric detectors of gravitational waves, namely Silica, Tantala, and Ti-dop ed Tantala, from direct measurement of coating thermal noise in an optical interferometer testbench, the Caltech TNI. We also present a simple predictive theory for the material properties of amorphous glassy oxide mixtures, which gives results in good agreement with our measurements on Ti-doped Tantala. Alternative measure ment methods and results are reviewed, and some critical issues are discussed.

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Maria Principe, Innocenzo M. Pinto, Vincenzo Pierro, Riccardo DeSalvo, Ilaria Taurasi, Akira E. Villar, Eric D. Black, Kenneth G. Libbrecht, Christophe Michel, Nazario Morgado, Laurent Pinard. 2015-01-26. Material loss angles from direct measurements of broadband thermal noise. https://doi.org/10.1103/physrevd.91.022005

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