Theoretical Research on LIGO Noise Reduction and Advanced Interferometer Configurations

该奖项支持与激光干涉引力波天文台（LIGO）相关的理论研究，旨在提高LIGO探测器的灵敏度。 在该项目期间进行的研究探索了引力波探测器的基础量子和引力物理学，其结果将与更广泛的量子光力学社区广泛相关。这个项目将在加州理工学院陈延北教授的研究小组进行，它将成为年轻引力波科学家的训练场-让他们接触各种研究课题，从量子测量理论到经典统计物理。具体来说，陈光诚的研究小组成员将与LIGO实验室的成员以及LIGO科学合作组的其他成员进行密切交流：（A）探索降低LIGO量子噪声的新技术，包括使用主动量子光机器件、利用多个光学模式产生的光学刚性以及可能的主动介质应用。所谓的能量量子极限的量子测量的适用范围将严格研究。(B)将对先进的干涉仪配置进行研究;特别是，将调查信号到达期间切换干涉仪配置的可行性和优点;将评估光学模式缺陷对校准的影响;将建立评估先进LIGO干涉仪升级策略的框架。(C)将对各向异性涂层材料和非平衡低温悬浮系统的热涨落进行理论研究。(D)将制定使用宏观测试质量和量子限制测量来测试基本量子和引力物理的策略。

This award supports theoretical research related to the Laser Interferometer Gravitational Wave Observatory (LIGO), with the aim of improving the sensitivity of LIGO detectors. Research carried out during this project explores the fundamental quantum and gravitational physics that underlie gravitational-wave detectors, and the results will be widely relevant to the more general community of quantum optomechanics. This project will be carried out at professor Yanbei Chen's research group at the California Institute of Technology; it will serve as a training ground for young gravitational-wave scientists --- by exposing them to a variety of research topics, ranging from quantum measurement theory to classical statistical physics. Members of Chen's research group will interact closely with members of the LIGO Lab, and the rest of the LIGO Scientific collaboration.More specifically: (A) New techniques of reducing LIGO's quantum noise will be explored, including the use of active quantum optomechanical devices, the employment of optical rigidity generated by multiple optical modes, and the possible application of active medium. The domain of applicability of the so-called Energetic Quantum Limit for quantum measurements will be critically studied. (B) Research on advanced interferometer configurations will be carried out; in particular, the feasibility and merit of switching interferometer configurations during signal arrival will be investigated; the effect of optical-mode imperfection on calibration will be evaluated; a framework for evaluating upgrade strategies for Advanced LIGO interferometers will be established. (C) Theoretical investigations on thermal fluctuations of anistoropic coating materials and non-equilibrium cryogenic suspension systems will be carried out. (D) Strategies of testing fundamental quantum and gravitational physics using macroscopic test masses and quantum-limited measurements will be formulated.