A new method of probing mechanical losses of coatings at cryogenic temperatures

Serge Galliou; Samuel Deléglise; Maxim Goryachev; Leonhard Neuhaus; Gianpietro Cagnoli; Salim Zerkani; Vincent Dolique; Xavier Vacheret; Philippe Abbé; Laurent Pinard; Christophe Michel; Thibaut Karassouloff; Tristan Briant; Pierre-François Cohadon; Antoine Heidmann; Michael E. Tobar; Roger Bourquin

doi:10.1063/1.4972106

arXiv · 1605.07697

A new method of probing mechanical losses of coatings at cryogenic temperatures

Serge Galliou·Samuel Deléglise·Maxim Goryachev·Leonhard Neuhaus·Gianpietro Cagnoli·Salim Zerkani·Vincent Dolique·Xavier Vacheret·Philippe Abbé·Laurent Pinard·Christophe Michel·Thibaut Karassouloff·Tristan Briant·Pierre-François Cohadon·Antoine Heidmann·Michael E. Tobar·Roger Bourquin

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Abstract

A new method of probing mechanical losses and comparing the corresponding deposition processes of metallic and dielectric coatings in 1-100 MHz frequency range and cryogenic temperatures is presented. The method is based on the use of extremely high-quality quartz acoustic cavities whose internal losses are orders of magnitude lower than any available coatings nowadays. The approach is demonstrated for Chromium, Chromium/Gold and a multilayer tantala/silica coatings. The ${\rm Ta}_2{\rm O}_5/{\rm Si}{\rm O}_2$ coating has been found to exhibit a loss angle lower than $1.6\times10^{-5}$ near 30 {\rm MHz} at 4 {\rm K}. The results are compared to the previous measurements.

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Serge Galliou, Samuel Deléglise, Maxim Goryachev, Leonhard Neuhaus, Gianpietro Cagnoli, Salim Zerkani, Vincent Dolique, Xavier Vacheret, Philippe Abbé, Laurent Pinard, Christophe Michel, Thibaut Karassouloff, Tristan Briant, Pierre-François Cohadon, Antoine Heidmann, Michael E. Tobar, Roger Bourquin. 2016-05-25. A new method of probing mechanical losses of coatings at cryogenic temperatures. https://doi.org/10.1063/1.4972106

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