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High reflectivity grating waveguide coatings for 1064nm

A. Bunkowski·O. Burmeister·D. Friedrich·K. Danzmann·R. Schnabel
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Abstract

We propose thin single-layer grating waveguide structures to be used as high-reflectivity, but low thermal noise, alternative to conventional coatings for gravitational wave detector test mass mirrors. Grating waveguide (GWG) coatings can show a reflectivity of up to 100% with an overall thickness of less than a wavelength. We theoretically investigate GWG coatings for 1064nm based on tantala (Ta2O5) on a Silica substrate focussing on broad spectral response and low thickness.

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A. Bunkowski, O. Burmeister, D. Friedrich, K. Danzmann, R. Schnabel. 2006-08-01. High reflectivity grating waveguide coatings for 1064nm. https://doi.org/10.1088/0264-9381%2F23%2F24%2F007

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