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arXiv · 1706.02928

Correlated evolution of structure and mechanical loss of a sputtered silica film

Massimo Granata·Elodie Coillet·Valérie Martinez·Vincent Dolique·Alex Amato·Maurizio Canepa·Jérémie Margueritat·Christine Martinet·Alain Mermet·Christophe Michel·Laurent Pinard·Benoît Sassolas·Gianpietro Cagnoli
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Abstract

Energy dissipation in amorphous coatings severely affects high-precision optical and quantum transducers. In order to isolate the source of coating loss, we performed an extensive study of Raman scattering and mechanical loss of a thermally-treated sputtered silica coating. Our results show that loss is correlated with the population of three-membered rings of Si-O$_4$ tetrahedral units, and support the evidence that thermal treatment reduces the density of metastable states separated by a characteristic energy of about 0.5 eV, in favour of an increase of the states separated by smaller activation energies. Finally, we conclude that three-fold rings are involved in the relaxation mechanisms only if they belong to more complex chain-like structures of 10 to 100 tetrahedra.

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Massimo Granata, Elodie Coillet, Valérie Martinez, Vincent Dolique, Alex Amato, Maurizio Canepa, Jérémie Margueritat, Christine Martinet, Alain Mermet, Christophe Michel, Laurent Pinard, Benoît Sassolas, Gianpietro Cagnoli. 2017-06-09. Correlated evolution of structure and mechanical loss of a sputtered silica film. https://doi.org/10.1103/physrevmaterials.2.053607

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