A new generation of gravitational wave detectors is currently being designed with the likely use of a different laser wavelength compared to current instruments. The estimation of the optical losses for this new wavelength is particularly relevant to derive the detector sensitivity and also to anticipate the optical performances of future instruments. In this article, we measured the absorption and angle-resolved scattering of several mirror samples in order to compare optical losses at a wavelength of 1064 and 1550 nm. In addition, we have carried out simulations of the Einstein Telescope arm cavities at 1064 and 1550 nm taking into account losses due to surface low-spatial frequency flatness. Our results suggest that optical losses as measured at 1064 nm are about twice as large as those at 1550 nm as predicted with a simple model.

中文翻译：

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爱因斯坦望远镜引力波探测器两种波长的臂腔光损耗比较


目前正在设计新一代引力波探测器，与目前的仪器相比，可能会使用不同的激光波长。估计这种新波长的光损耗对于推导出探测器灵敏度以及预测未来仪器的光学性能特别相关。在本文中，我们测量了几个反射镜样品的吸收和角度分辨散射，以比较 1064 和 1550 nm 波长下的光损耗。此外，我们还在 1064 和 1550 nm 处对爱因斯坦望远镜臂腔进行了模拟，同时考虑了表面低空间频率平坦度造成的损耗。我们的结果表明，在 1064 nm 处测得的光损耗大约是用简单模型预测的 1550 nm 处光损耗的两倍。