论文标题
精确干涉仪中的非几何倾斜到长度耦合：机制和分析描述
Non-geometric tilt-to-length coupling in precision interferometry: mechanisms and analytical descriptions
论文作者
论文摘要
本文是两个研究倾斜长度（TTL）耦合组中的第二篇。 TTL描述了角度或翻译抖动到干涉相信号中的交叉耦合，并且是精确干涉仪（包括丽莎之类的空间引力波检测器）中的重要噪声源。我们在10.1088/2040-8986/ac675e中讨论了源自光路长度变化的TTL耦合效应，即几何TTL耦合。在这项工作中，在两个干扰基本的高斯梁的情况下，我们专注于波前和检测器几何依赖性TTL耦合，称为非几何TTL耦合。我们表征源自干扰梁的性质的耦合，即它们在检测器的绝对角度和相对角度，它们的相对偏移和单个梁参数。此外，我们讨论了TTL耦合对检测光电二极管几何形状的依赖性。尽可能，我们为预期的TTL耦合效应提供分析表达式。我们研究了由于镜子或接收系统的角度或翻译抖动而源自光束行走的非几何耦合效应。将这些效果直接与10.1088/2040-8986/AC675E中相应检测到的光路长度变化进行比较。两者一起提供总干涉读数。我们在哪种情况下讨论几何和非几何TTL效应取消了一对一。此外，我们列出了可用于抵消其他TTL效应的线性TTL贡献。总体而言，我们的结果提供了关键知识，以最大程度地减少通过设计或重新调整实验中TTL耦合噪声的最大程度。
This paper is the second in a set of two investigating tilt-to-length (TTL) coupling. TTL describes the cross-coupling of angular or translational jitter into an interferometric phase signal and is an important noise source in precision interferometers, including space gravitational wave detectors like LISA. We discussed in 10.1088/2040-8986/ac675e the TTL coupling effects originating from optical path length changes, i.e. geometric TTL coupling. Within this work, we focus on the wavefront and detector geometry dependent TTL coupling, called non-geometric TTL coupling, in the case of two interfering fundamental Gaussian beams. We characterise the coupling originating from the properties of the interfering beams, i.e. their absolute and relative angle at the detector, their relative offset and the individual beam parameters. Furthermore, we discuss the dependency of the TTL coupling on the geometry of the detecting photodiode. Wherever possible, we provide analytical expressions for the expected TTL coupling effects. We investigate the non-geometric coupling effects originating from beam walk due to the angular or translational jitter of a mirror or a receiving system. These effects are directly compared with the corresponding detected optical path length changes in 10.1088/2040-8986/ac675e. Both together provide the total interferometric readout. We discuss in which cases the geometric and non-geometric TTL effects cancel one-another. Additionally, we list linear TTL contributions that can be used to counteract other TTL effects. Altogether, our results provide key knowledge to minimise the total TTL coupling noise in experiments by design or realignment.
