Cryogenic mechanical loss measurements of heat-treated hafnium dioxide

Abernathy, M.R. et al. (2011) Cryogenic mechanical loss measurements of heat-treated hafnium dioxide. Classical and Quantum Gravity, 28(19), p. 195017. (doi: 10.1088/0264-9381/28/19/195017)

Abstract

Low mechanical loss, high index-of-refraction thin-film coating materials are of particular interest to the gravitational wave detection community, where reduced mirror coating thermal noise in gravitational wave detectors is desirable. Current studies are focused on understanding the loss of amorphous metal oxides such as SiO(2), Ta(2)O(5) and HfO(2). Here, we report recent measurements of the temperature dependence of the mechanical loss of ion-beam sputtered hafnium dioxide (HfO(2)) coatings that have undergone heat treatment. The results indicate that, even when partially crystallized, these coatings have lower loss than amorphous Ta(2)O(5) films below similar to 100 K and that their loss exhibits some features which are heat-treatment dependent in the temperature range of similar to 100-200 K, with higher heat treatment yielding lower mechanical loss. The potential for using silica doping of hafnia coatings to prevent crystallization is discussed.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Rowan, Professor Sheila and Abernathy, Mr Matthew and Martin, Dr Iain and Hough, Professor James and MacLaren, Dr Ian and Reid, Professor Stuart and Bassiri, Mr Riccardo and Murray, Dr Peter
• Authors: Abernathy, M.R., Reid, S., Chalkley, E., Bassiri, R., Martin, I.W., Evans, K., Fejer, M.M., Gretarsson, A., Harry, G.M., Hough, J., MacLaren, I., Markosyan, A., Murray, P., Nawrodt, R., Penn, S., Route, R., Rowan, S., and Seidel, P.
• Subjects: Q Science > QC Physics
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Research Centre: College of Science and Engineering > School of Physics and Astronomy > Institute for Gravitational Research
• Journal Name: Classical and Quantum Gravity
• Publisher: Institute of Physics
• ISSN: 0264-9381
• Published Online: 14 September 2011