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arXiv · 1511.06172

Mechanical loss in state-of-the-art amorphous optical coatings

Massimo Granata·Emeline Saracco·Nazario Morgado·Alix Cajgfinger·Gianpietro Cagnoli·Jérôme Degallaix·Vincent Dolique·Danièle Forest·Janyce Franc·Christophe Michel·Laurent Pinard·Raffaele Flaminio
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Abstract

We present the results of mechanical characterizations of many different high-quality optical coatings made of ion-beam-sputtered titania-doped tantala and silica, developed originally for interferometric gravitational-wave detectors. Our data show that in multi-layer stacks (like high-reflection Bragg mirrors, for example) the measured coating dissipation is systematically higher than the expectation and is correlated with the stress condition in the sample. This has a particular relevance for the noise budget of current advanced gravitational-wave interferometers, and, more generally, for any experiment involving thermal-noise limited optical cavities.

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Massimo Granata, Emeline Saracco, Nazario Morgado, Alix Cajgfinger, Gianpietro Cagnoli, Jérôme Degallaix, Vincent Dolique, Danièle Forest, Janyce Franc, Christophe Michel, Laurent Pinard, Raffaele Flaminio. 2016-01-21. Mechanical loss in state-of-the-art amorphous optical coatings. https://doi.org/10.1103/physrevd.93.012007

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