RUI: Advancing Gravitational-Wave Optics to Further Explore the Cosmos

RUI：推进引力波光学进一步探索宇宙

• 批准号: 2207998
• 负责人: Joshua Smith
• 金额: $ 35.57万
• 依托单位: CSU Fullerton Auxiliary Services Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2207998&HistoricalAwards=false
• 关键词: RUI; Advancing; Gravitational; Wave; Optics

This award supports research in relativity and relativistic astrophysics, and it addresses the priority areas of NSF's "Windows on the Universe" Big Idea. Albert Einstein predicted gravitational waves as a consequence of general relativity in 1916. A century later, the NSF-funded Laser Interferometer Gravitational-Wave Observatory (LIGO) opened a new window on the universe by observing gravitational waves from merging black holes. LIGO and its international partners Virgo and Kagra have since detected gravitational waves from nearly 100 systems. Work is underway to extend the reach of LIGO through the Advanced LIGO+ (A+) upgrades and a potential cryogenic silicon detector, Voyager. A next-generation US observatory, Cosmic Explorer, is also being developed. These detectors will use optical technology to peer deeply into the universe’s dark side and open a wide discovery aperture to the novel and unknown. This project will engage students and faculty at California State University, Fullerton (CSUF) in experimental research aimed at advancing optical technology to further explore the cosmos with gravitational waves. Students and the PI will characterize and develop techniques to reduce the amount of laser light scattered by optical coatings. They will measure the optical scattering of silicon at cryogenic temperatures and estimate its effects on gravitational-wave detector performance. They will map the laser light loss due to birefringence of silicon, at the wavelength and temperature planned for Voyager and possible cryogenic realizations of Cosmic Explorer, for the first time. These studies will help A+ to double the rate of gravitational-wave observations and Voyager and Cosmic Explorer to observe black hole and neutron star collisions to the era of the first stars. This work will additionally contribute to the field of optics and potentially lead to improvements in commercial optics. Conducting this research at CSUF will have a disproportionately positive impact on students from groups traditionally underrepresented in physics.This project will engage students and faculty at California State University, Fullerton (CSUF) in experimental research aimed at advancing optical technology to further explore the cosmos with gravitational waves. To achieve their goals, A+ and Cosmic Explorer require room-temperature optical coatings for 1-micron-wavelength laser light that have improved thermal noise, with still excellent optical properties, including optical scatter. Heat treatment (annealing) of coatings has been shown to decrease both their thermal noise and optical scatter. Students and the PI will employ an annealing scatterometer and an angle-resolved scatterometer to characterize and develop techniques to reduce scattering from the most promising coatings. Voyager technology could extend the reach of LIGO and Cosmic Explorer by reducing thermal noise and thermal aberrations using crystalline silicon optics operated at cryogenic temperatures (123 K, a zero crossing of silicon’s thermal expansion coefficient). The PI and students will use a cryogenic testbed to measure the surface, bulk, and coated optical scattering for high-purity crystalline silicon at cryogenic temperatures and estimate its effects on gravitational-wave detector performance. Optical losses due to birefringence in these transparent crystalline silicon optics could also decrease the astrophysical reach of future detectors. The PI and students will map the birefringence of crystalline silicon at 2-micron-wavelength and 123 K for the first time, using an optical cavity. These studies will help A+ to double the rate of gravitational-wave observations and Voyager and possible cryogenic realizations of Cosmic Explorer to observe black hole and neutron star collisions to the era of the first stars.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项支持相对论和相对论天体物理学的研究，并解决了 NSF“宇宙之窗”大构想的优先领域，阿尔伯特·爱因斯坦在 1916 年预测引力波是广义相对论的结果。一个世纪后，NSF 资助的激光项目诞生了。干涉仪引力波天文台 (LIGO) 通过观测来自合并黑洞的引力波，打开了观察宇宙的新窗口。自此，国际合作伙伴 Virgo 和 Kagra 已经探测到来自近 100 个系统的引力波，并正在通过先进的 LIGO+ (A+) 升级和潜在的低温硅探测器 Voyager 来扩大 LIGO 的覆盖范围。这些探测器也正在开发中，将利用光学技术深入观察宇宙的黑暗面，为新奇和未知的事物打开一个广阔的发现空间。该项目将吸引加州州立大学的学生和教师。富勒顿大学 (CSUF) 开展实验研究，旨在推进光学技术，进一步利用引力波探索宇宙。学生和 PI 将表征和开发减少光学涂层散射的激光量的技术。他们将在 Voyager 计划的波长和温度以及 Cosmic 可能的低温实现下绘制由于硅的双折射而导致的激光光损失，并估计其对引力波探测器性能的影响。这些研究将首次帮助 A+ 将引力波观测速度提高一倍，而 Voyager 和 Cosmic Explorer 观测黑洞和中子星碰撞到第一颗恒星的时代也将对该领域做出额外贡献。在 CSUF 进行这项研究将对光学领域传统上代表性不足的群体的学生产生不成比例的积极影响。该项目将吸引加州州立大学富勒顿分校的学生和教师。 (CSUF) 的实验研究旨在推进光学技术，以利用引力波进一步探索宇宙。为了实现其目标，A+ 和 Cosmic Explorer 需要用于 1 微米波长激光的室温光学涂层，以改善热噪声。仍然具有优异的光学性能，包括涂层的热处理（退火）已被证明可以降低其热噪声和光学散射。学生和 PI 将使用退火散射仪和角度分辨仪。 Voyager 技术可以通过使用在低温（123 K，硅的零交叉）下运行的晶体硅光学器件来减少热噪声和热畸变，从而扩展 LIGO 和 Cosmic Explorer 的覆盖范围。 PI 和学生将使用低温测试台测量低温下高纯晶体硅的表面、体积和涂层光学散射，并估计其对热膨胀系数的影响。这些透明晶体硅光学器件中的双折射造成的光学损失也可能会降低未来探测器的天体物理范围。PI 和学生将首次绘制 2 微米波长和 123 K 下晶体硅的双折射图。随着时间的推移，这些研究将帮助 A+ 将引力波观测速度提高一倍，而 Voyager 以及 Cosmic Explorer 可能实现的低温观测黑洞和中子星碰撞到第一颗恒星时代。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Imaging scatterometer for observing in situ changes to optical coatings during air annealing

成像散射仪用于观察空气退火过程中光学涂层的原位变化

• DOI: 10.1364/ao.476979
• 发表时间: 2023
• 期刊: Applied Optics
• 影响因子: 1.9
• 作者: Rezac, Michael;Martinez, Daniel;Gleckl, Amy;Smith, Joshua R.
• 通讯作者: Smith, Joshua R.