Ultra-low noise meta-mirrors with optical losses below 500 ppm

Abstract

Interferometric experiments are often limited in sensitivity by the thermal noise of the mirrors. In particular, interferometric gravitational wave detectors and laser stabilization resonators can benefit from reduced mirror noise. We present results of experimental investigations on micro-structured mirrors (meta-mirrors) and hybrid etalon mirrors (meta-etalons) promising particularly low thermal noise. We show the first characterization of meta-etalons scattering and absorption losses, demonstrating optical losses below 500 ppm. This level of optical losses is sufficient for planning direct thermal noise measurement in dedicated optical cavity experiments. These measurements would be very important for validating the thermal noise predictions. We present our development toward the integration of meta-etalons in ultra-stable optical cavities.