Material loss angles from direct measurements of broadband thermal noise

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.

References in corpus (12)

• LIGO: The Laser Interferometer Gravitational-Wave Observatory
• Detector configuration of KAGRA - the Japanese cryogenic gravitational-wave detector
• Thermal noise in interferometric gravitational wave detectors due to dielectric optical coatings
• IndIGO and LIGO-India: Scope and Plans for Gravitational Wave Research and Precision Metrology in India
• Titania-doped tantala/silica coatings for gravitational-wave detection
• Mechanical Loss in Tantala/Silica Dielectric Mirror Coatings
• Thermodynamical fluctuations in optical mirror coatings
• Measurement of Thermal Noise in Multilayer Coatings with Optimized Layer Thickness
• Quadrature phase interferometer for high resolution force spectroscopy
• Direct Observation of Broadband Coating Thermal Noise in a Suspended Interferometer
• Measurements of mechanical thermal noise and energy dissipation in optical dielectric coatings
• Investigation of the Young's modulus and thermal expansion of amorphous titania-doped tantala films

Cited by in corpus (15)

• Amorphous optical coatings of present gravitational-wave interferometers
• Mechanical loss in state-of-the-art amorphous optical coatings
• Superfluid Brillouin Optomechanics
• Microfabrication of large area high-stress silicon nitride membranes for optomechanical devices
• Direct Measurement of Coating Thermal Noise in Optical Resonators
• Structure and morphology of low mechanical loss TiO${}_2$-doped Ta${}_2$O${}_5$
• Audio-band Coating Thermal Noise Measurement for Advanced LIGO with a Multi-mode Optical Resonator
• Correlated evolution of structure and mechanical loss of a sputtered silica film
• Electric noise spectra of a near-surface nitrogen vacancy center diamond with a protective layer
• Brownian Thermal Noise in Functional Optical Surfaces
• Highly reflective low-noise etalon-based meta-mirror
• Minimum Noise Optical Coatings for Interferometric Detectors of Gravitational Waves
• Fabry -Perot filters with Tunable Josephson Junction Defects
• A new method of probing mechanical losses of coatings at cryogenic temperatures
• Switching Times in Fabry-Perot Measurements