Development of mirror coatings and test-mass substrates for future gravitational wave detectors

自2015年首次探测到引力波以来，已经探测到40多个黑洞合并事件，两个中子星合并和两个黑洞/中子开始合并，为这些天体提供了新的天体物理学见解。未来，更灵敏的引力波探测器计划允许从更广泛的来源观测更多的信号。当前探测器的一个关键灵敏度限制是热噪声——探测器反射镜由于其温度引起的振动。该项目旨在开发具有低热噪声和极高光学性能的新型反射镜材料，用于未来的室温和低温探测器。该项目将特别侧重于镜面基板的光学吸收和光学散射以及应用于其上的高反射涂层。低光吸收对于维持低温反射镜温度和防止反射镜热变形至关重要。低光散射是防止杂散光噪声效应的必要条件。本研究的主要应用是未来的引力波探测器，以及对现有探测器的升级。然而，这项工作也与光学涂层行业相关，其中许多应用需要具有低吸收和高耐受性的极端性能涂层，并且该项目与新成立的极端性能光学涂层中心（EPOC）有许多协同作用，该中心位于格拉斯哥，是苏格兰国家制造研究所（NMIS）的一部分，NMIS投入了大量资金。斯特拉斯克莱德大学和格拉斯哥大学。

Following the first detection of gravitational waves in 2015, over 40 black hole merger events, two neutron star mergers and two black-hole/neutron start mergers have been detected, providing new astrophysical insight into these bodies. Future, more sensitive, gravitational wave detectors are planned to allow observation of more signals, from a wider variety of sources. One of the critical sensitivity limits to current detectors is thermal noise - vibrations in the detector mirrors due to their temperature. This project aims to develop new mirror materials, with low thermal noise and extremely high optical performance, for application in future detectors operating at room-temperature and at cryogenic temperature. The project will focus particularly on the optical absorption and optical scattering of mirror substrates and the highly reflective coatings applied to them. Low optical absorption is essential to maintain cryogenic mirror temperatures and prevent thermal deformations of the mirrors. Low optical scattering is essential to prevent noise effects from stray light. The main application of this research is future gravitational wave detectors, and upgrades to current detectors. However, this work is also of relevance to the optical coatings industry, where many applications require extreme performance coatings with low absorption and high tolerance to laser-induced damage, and the project has many synergies with the newly established Centre for Extreme Performance Optical Coatings (EPOC) being set up in Glasgow, as part of the National Manufacturing Institute Scotland (NMIS), with significant investment from NMIS, the University of Strathclyde and the University of Glasgow.