We present a noise estimation and subtraction algorithm capable of increasing the sensitivity of heterodyne laser interferometers by one order of magnitude. The heterodyne interferometer is specially designed for dynamic measurements of a test mass in the application of sub-Hz inertial sensing. A noise floor of 3.31E-11 m/rtHz at 100mHz is achieved after applying our noise subtraction algorithm to a benchtop prototype interferometer that showed a noise level of 2.76E-10 m/rtHz at 100mHz when tested in vacuum at levels of 3E-5 Torr. Based on the previous results, we investigated noise estimation and subtraction techniques of non-linear optical pathlength noise, laser frequency noise, and temperature fluctuations in heterodyne laser interferometers. For each noise source, we identified its contribution and removed it from the measurement by linear fitting or a spectral analysis algorithm. The noise correction algorithm we present in this article can be generally applied to heterodyne laser interferometers.
Quasi-monolithic heterodyne laser interferometer for inertial sensing
我们提出了一种紧凑的外差激光干涉仪开发的高灵敏度位移传感应用。这种干涉仪由定制的棱镜和波片组装成一个准单片单元，以实现小型化系统。干涉仪设计采用共模抑制方案，对常见环境噪声提供高抑制比。真空中的实验测试表明，位移灵敏度水平为11 pm/rtHz在100 mHz，和低至0.6 pm/rtHz以上的1 Hz。该原型装置的尺寸为20 mm X 20 mm X 10 mm，重4.5克，可随后集成到紧凑型系统中。
Tracking length and differential wavefront sensing signals from quadrant photodiodes in heterodyne interferometers with digital phase-locked loop readout
In situ substrate birefringence characterization in gravitational wave detectors using a heterodyne polarimetry method
Cardiff University（卡迪夫大学）；The University of Tokyo（东京大学）；University of Birmingham（伯明翰大学）；Nikhef, National Institute for Subatomic Physics（荷兰国家亚原子物理研究所）；University of Glasgow（格拉斯哥大学）；Universit‘ a di Trento（特伦托大学）
Progress towards ultracold Sr for the AION project -- sub-microkelvin atoms and an optical-heterodyne diagnostic tool for injection-locked laser diodes
Experimental Demonstration of an On-Axis Laser Ranging Interferometer for Future Gravity Missions
Max-Planck-Institut für Gravitationsphysik (Albert-Einstein-Institut)（马克斯·普朗克引力物理研究所（爱因斯坦研究所））；Leibniz Universität Hannover（汉诺威莱布尼茨大学）；Center for Space Sciences and Technology, University of Maryland, Baltimore County（马里兰大学巴尔的摩县分校太空科学与技术中心）；Gravitational Astrophysics Lab, NASA/GSFC（NASA/戈达德太空飞行中心引力天体物理实验室）；Center for Research and Exploration in Space Science and Technology, NASA/GSFC（NASA/戈达德太空飞行中心空间科学与技术研究探索中心）；Wyant College of Optical Sciences, University of Arizona（亚利桑那大学怀安特光学学院）
Reducing the Virgo site infrastructure noise in preparation of the O4 observing run
European Gravitational Observatory (EGO)（欧洲引力观测站）；INFN, Sezione di Pisa（意大利国家核物理研究所比萨分部）；Università di Pisa（比萨大学）；INFN, Sezione di Roma（意大利国家核物理研究所罗马分部）；INFN, Sezione di Firenze（意大利国家核物理研究所佛罗伦萨分部）；Università di Firenze（佛罗伦萨大学）；Università degli Studi di Urbino “Carlo Bo”（乌尔比诺卡尔洛·博大学）
