Novel Method to Measure the Gravitational Constant

测量引力常数的新方法

• 批准号: 21K03603
• 负责人: Zeidler Simon
• 金额: $ 2.66万
• 依托单位: Rikkyo University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2021
• 资助国家: 日本
• 起止时间: 2021-04-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-21K03603/
• 关键词: polarization stability; noise; coherence; Interferometer; Mach-Zehnder; Laser; Gravity

I succeeded to build a laser Doppler-interferometer, connected to a high-speed sampling oscilloscope, with which oscillation-amplitudes at 1~5kHz below picometer-ranges (<10^-12 m) could be measured. The first attempt of building such an instrument lagged clearly in polarization stability as the measured ground noise could not be lowered below 1pm/Hz^(1/2) even with a maximum sampling rate of 5MHz. The last measured ground noise is now at 0.13pm/Hz^(1/2).The instrument has experienced upgrades regarding the polarization stability in the form of Glan-Taylor prisms which are now in front of the waveplates on the recombining beam-splitter side and a Faraday isolator at the laser-input. Furthermore, care has been taken to ensure an equal optical path length for both the reference and the signal beam path by using polarization maintaining fibers. This increased the coherence of both beams and thus also the contrast of the observed fringes at the detectors.One minor aspect of the conducted research was to ensure the usability of the Piezo-test chip even for oszillation amplitudes below a picometer. This is important to keep the dynamic constrast low and thus the resolution of the measurements high. The results clearly proof the capability of the test-chip.

我成功地构建了一个激光多普勒干涉仪，连接到高速采样示波器，可以测量皮米范围（<10^-12 m）以下1~5kHz的振荡幅度。建造这种仪器的第一次尝试在极化稳定性方面明显滞后，因为即使在最大采样率为 5MHz 的情况下，测量的地面噪声也无法降至 1pm/Hz^(1/2) 以下。最后测量的地面噪声现在为 0.13pm/Hz^(1/2)。该仪器以格兰泰勒棱镜的形式经历了偏振稳定性的升级，这些棱镜现在位于重组分束器上的波片前面侧和激光输入处的法拉第隔离器。此外，还注意通过使用保偏光纤来确保参考光路和信号光路的光路长度相等。这增加了两束光束的相干性，从而增加了探测器处观察到的条纹的对比度。所进行的研究的一个小方面是确保压电测试芯片的可用性，即使振荡幅度低于皮米。这对于保持较低的动态对比度以及较高的测量分辨率非常重要。结果清楚地证明了测试芯片的能力。

项目成果

Sub-nm Amplitude Detector Construction for Newton-V Microgravity Measurement

用于牛顿 V 微重力测量的亚纳米振幅探测器结构

• 发表时间: 2022
• 作者: Simon Zeidler

Novel Method to Measure Gravity at small Distances

短距离测量重力的新方法

• 发表时间: 2021
• 作者: Simon Zeidler;渡邉丈晃;Simon Zeidler;Daisuke Ikeda;Simon Zeidler
• 通讯作者: Simon Zeidler

The Search for Deviations from Newton’s Gravity at Micrometer Scales

寻找微米尺度上牛顿引力的偏差

• 发表时间: 2022
• 作者: Simon Zeidler;渡邉丈晃;Simon Zeidler
• 通讯作者: Simon Zeidler