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arXiv · 1004.1223

Measurement of Thermal Noise in Multilayer Coatings with Optimized Layer Thickness

Akira E. Villar·Eric D. Black·Riccardo DeSalvo·Kenneth G. Libbrecht·Christophe Michel·Nazario Morgado·Laurent Pinard·Innocenzo M. Pinto·Vincenzo Pierro·Vincenzo Galdi·Maria Principe·Ilaria Taurasi
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Abstract

A standard quarter-wavelength multilayer optical coating will produce the highest reflectivity for a given number of coating layers, but in general it will not yield the lowest thermal noise for a prescribed reflectivity. Coatings with the layer thicknesses optimized to minimize thermal noise could be useful in future generation interferometric gravitational wave detectors where coating thermal noise is expected to limit the sensitivity of the instrument. We present the results of direct measurements of the thermal noise of a standard quarter-wavelength coating and a low noise optimized coating. The measurements indicate a reduction in thermal noise in line with modeling predictions.

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Akira E. Villar, Eric D. Black, Riccardo DeSalvo, Kenneth G. Libbrecht, Christophe Michel, Nazario Morgado, Laurent Pinard, Innocenzo M. Pinto, Vincenzo Pierro, Vincenzo Galdi, Maria Principe, Ilaria Taurasi. 2010-04-08. Measurement of Thermal Noise in Multilayer Coatings with Optimized Layer Thickness. https://doi.org/10.1103/physrevd.81.122001

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