Improving the stability of frequency-dependent squeezing with bichromatic control of filter cavity length, alignment, and incident beam pointing
Improving the stability of frequency-dependent squeezing with bichromatic control of filter cavity length, alignment, and incident beam pointing
复制标题
DOI：
10.1103/physrevd.105.082003
复制
发表时间：
2022-03
影响因子：
5
通讯作者：
Yuhang Zhao;E. Capocasa;M. Eisenmann;N. Aritomi;M. Page;Yuefan Guo;E. Polini;K. Arai;Y. Aso;M. van Beuzekom;Yao-Chin Huang;Ray-Kuang Lee;H. Lück;O. Miyakawa;P. Prat;A. Shoda;M. Tacca;R. Takahashi;H. Vahlbruch;M. Vardaro;Chien‐Ming Wu;M. Leonardi;M. Barsuglia;R. Flaminio
中科院分区：
文献类型：
--
作者：
Yuhang Zhao;E. Capocasa;M. Eisenmann;N. Aritomi;M. Page;Yuefan Guo;E. Polini;K. Arai;Y. Aso;M. van Beuzekom;Yao-Chin Huang;Ray-Kuang Lee;H. Lück;O. Miyakawa;P. Prat;A. Shoda;M. Tacca;R. Takahashi;H. Vahlbruch;M. Vardaro;Chien‐Ming Wu;M. Leonardi;M. Barsuglia;R. Flaminio
频率相关挤压是在即将进行的引力波探测器观测中实现宽带量子噪声降低的主要升级。压缩正交的正确频率依赖性是通过反射来自法布里-珀罗滤波器腔的压缩真空而获得的，法布里-珀罗滤波器腔失谐了其线宽的一半。然而，由于压缩真空不包含经典振幅，因此需要共同传播的辅助控制光束来实现滤光腔的长度、对准和入射光束指向稳定性。在日本国家天文台的频率相关挤压实验中，我们使用压缩真空波长谐波的控制光束，发现与悬挂镜角漂移相关的可见失谐变化。这些变化会降低干涉仪量子降噪效果。我们研究了可能导致滤波器腔失谐变化的各种机制。发现通过固定入射光束指向并应用滤光腔自动对准可以充分减轻失谐漂移。研究还发现，光束在滤光腔镜上存在一个最佳位置，有助于减少失谐波动。在这里，我们报告了与 113$\,$Hz 腔线宽相比，稳定的滤波器腔失谐变化小于 10$\,$Hz。与之前发表的结果相比[Phys。莱特牧师。 124, 171101 (2020)]，这样的失谐稳定性足以使滤腔失谐漂移引起的引力波探测器探测范围波动从$11\%$减少到$2\%$以内。
Frequency dependent squeezing is the main upgrade for achieving broadband quantum noise reduction in upcoming observation runs of gravitational wave detectors. The proper frequency dependence of the squeezed quadrature is obtained by reflecting squeezed vacuum from a Fabry-Perot filter cavity detuned by half of its linewidth. However, since the squeezed vacuum contains no classical amplitude, co-propagating auxiliary control beams are required to achieve the filter cavity's length, alignment, and incident beam pointing stability. In our frequency dependent squeezing experiment at the National Astronomical Observatory of Japan, we used a control beam at a harmonic of squeezed vacuum wavelength and found visible detuning variation related to the suspended mirrors angular drift. These variations can degrade interferometer quantum noise reduction. We investigated various mechanisms that can cause the filter cavity detuning variation. The detuning drift is found to be mitigated sufficiently by fixing the incident beam pointing and applying filter cavity automatic alignment. It was also found that there is an optimal position of the beam on the filter cavity mirror that helps to reduce the detuning fluctuations. Here we report a stabilized filter cavity detuning variation of less than 10$\,$Hz compared to the 113$\,$Hz cavity linewidth. Compared to previously published results [Phys. Rev. Lett. 124, 171101 (2020)], such detuning stability would be sufficient to make filter cavity detuning drift induced gravitational wave detector detection range fluctuation reduce from $11\%$ to within $2\%$.