Nonclassical Interferometry towards Gravitational-Wave Detectors at a Laser Wavelength of 2.1um

2.1um 激光波长下引力波探测器的非经典干涉测量

• 批准号: 388405737
• 负责人: Professor Dr. Roman Schnabel, since 8/2019
• 金额: --
• 依托单位: Institut für Laser-Physik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2017
• 资助国家: 德国
• 起止时间: 2016-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/388405737?language=en
• 关键词: Nonclassical; Interferometry; towards; Gravitational; Wave

The recent direct observation of gravitational waves from a binary black-hole merger has marked the beginning of gravitational-wave astronomy. To enable a continuous stream of detections with a high signal-to-noise ratio, upcoming generations of gravitational-wave detectors, which are based on the principle of laser interferometry, will aim at an increase of strain sensitivity by at least an order of magnitude. Through most of the detection band, the limiting noise sources are given by thermal noise in the mirror coatings and substrates, as well as quantum noise of the laser light field. Future detectors foresee a change to crystalline silicon as mirror material and operation at cryogenic temperatures. This will need to be accompanied by a change in laser wavelength to around 2µm, from the currently used 1µm. At the same time, squeezed states of light have been successfully shown to reduce the quantum noise in gravitational-wave detectors. Combining these two advancements is therefore a major step towards a successful era of gravitational-wave astronomy. So far, laser development at around 2µm has been driven by LIDAR and medical applications, therefore little experience exists with the demanding stability requirements for high-power lasers in gravitational-wave detectors. Furthermore, squeezed light has not been demonstrated at 2µm, and photo detectors with a near-unity quantum efficiency - so as to not destroy the fragile nonclassical correlations in the squeezed field - are not yet available.The project team will develop a complete solution for 2µm laser technology aimed at gravitational-wave detection that is solely based on degenerate parametric down-conversion of the existing highly stable 1064nm laser sources. Within this project, we will develop a squeezed-light source at 2.128µm, demonstrating for the first time that this wavelength is compatible with advanced quantum-noise reduction techniques. In addition, we will show compensation of detection loss by optical parametric amplification, partly removing the need for photo detectors with almost perfect quantum efficiency. The results of this work will thus play a significant role in planning and enabling future gravitational-wave detectors, pushing the boundaries of the observable universe.

最近直接观察了来自二元黑洞合并的重力波，这标志着引力波天文学的开始。为了启用具有高信噪比的连续检测流，即将基于激光干扰原理的后代重力波检测器将至少提高应变敏感性，至少将其提高数量级。通过大多数检测带，限制噪声源是由镜涂层和底物中的热噪声以及激光光场的量子噪声给出的。未来的探测器可以预见到将晶体硅的变化作为镜子的材料和低温温度下的操作。这将需要伴随着从目前使用的1µm的激光波长将激光波长变为约2µm。同时，已成功证明了挤压光状态以减少重力波检测器中的量子噪声。因此，将这两个进步结合在一起是迈向成功的引力波天文学时代的重要一步。到目前为止，激光大约2µm的激光开发是由激光雷达和医疗应用驱动的，因此在重力波探测器中，对高功率激光的稳定性要求的经验很少。 Furthermore, squeezed light has not been demonstrated at 2µm, and photo detectors with a near-unity quantum efficiency - so as To not destroy the fragile nonclassical correlations in the squeezed field - are not yet available.The project team will develop a complete solution for 2µm laser technology aimed at gravitational-wave detection that is solely based on degenerate parametric down-conversion of the existing highly stable 1064nm激光来源。在该项目中，我们将在2.128µm处开发一个挤压光源，这首先证明该波长与先进的量子噪声还原技术兼容。此外，我们将通过光学参数放大来显示检测损失的补偿，部分消除了对几乎完美量子效率的照片探测器的需求。因此，这项工作的结果将在计划和实现未来的重力波探测器方面发挥重要作用，从而推动可观察到的宇宙的界限。

项目成果

NQontrol: An open-source platform for digital control-loops in quantum-optical experiments.

NQontrol：量子光学实验中数字控制回路的开源平台

• DOI: 10.1063/1.5135873
• 发表时间: 2020
• 期刊: The Review of scientific instruments
• 作者: C. Darsow-Fromm;L. Dekant;S. Grebien;M. Schröder;R. Schnabel;S. Steinlechner
• 通讯作者: S. Steinlechner