Collaborative Research: Stanford-Florida program in Support of LIGO on Coatings and Core Optics

合作研究：斯坦福大学-佛罗里达州支持 LIGO 涂层和核心光学器件的项目

• 批准号: 1707964
• 负责人: Hai-Ping Cheng
• 金额: $ 24万
• 依托单位: University of Florida
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-12-01 至 2021-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1707964&HistoricalAwards=false
• 关键词: Collaborative; Research; Stanford; Florida; program

The detections of gravitational waves from coalescing black holes by the Advanced LIGO detectors has launched the field of gravitational wave astronomy. Increasing the sensitivity of the LIGO detector several times would increase the number of gravitational waves and the types of events observed. Future detectors, such as the A+ LIGO detector, planned for 2021, will be limited by thermal noise associated with the mirror coatings used in the detector optics. The proposed work is a collaborative effort between Martin Fejer's group at Stanford University and Hai-Ping Cheng's group at the University of Florida to develop mirror coatings with lower thermal noise to address this problem for A+ LIGO and beyond. The Stanford gravitational wave research program has been involved for more than two decades in research to enable gravitational wave detectors by working closely with the LIGO Science Collaboration (LSC) to do critical research and mitigate difficult challenges. In the past, Stanford has contributed broadly to the development of novel interferometer components and design, detailed studies of the optics and mitigating optical and thermal noise, and the advanced seismic isolation systems used in Advanced LIGO (aLIGO). Hai-Ping Cheng's group at Florida is involved in computational materials simulations. In support of LIGO, she has modeled atomic structure of amorphous films and evaluated mechanical losses associated with those structures as part of a broader LSC effort to develop low-thermal-noise mirror coatings. While Advanced LIGO has now operated with adequate sensitivity to detect black hole coalescences, its mid-band sensitivity will be limited by thermal noise resulting from mechanical dissipation in the mirror coatings. Stanford has had a leading role within the LSC in developing experimental methods to characterize the optical, elastic, and structural properties of the amorphous materials composing multilayer dielectric mirrors. Florida carries out the current computational materials modeling effort within LSC. The proposed program is a synergistic teaming to combine these skill sets to address a critical issue to meet the design goals of A+ LIGO, developing mirrors with 2-4 times less mechanical loss than the best currently available. The mechanical losses in amorphous materials depend on subtle, preparation-dependent features in their atomic structure. Data on these structural features obtained via the electron diffraction and X-ray scattering methods proposed here is challenging to interpret, as are molecular dynamics predictions of the structure. Methods exist to use the modeling to help interpret the data and the data to help constrain the modeling, which led to the teaming arrangement proposed here. The structural data and predictions for dependence of elastic losses on material composition and process conditions, will become a major contributor to the broader LSC program to develop mirrors for A+ LIGO, guiding the others working on this problem through the thicket of possible synthesis and characterization experiments. Another long-standing effort at Stanford has been in the optical characterization of low-optical loss materials at the sub-ppm/cm level, dating back to the selection between silica and sapphire for initial LIGO test masses. The group has recently begun using the interferometric tool developed for those studies to characterize cryogenic losses in single-crystal silicon samples to evaluate their suitability as test masses in the planned cryogenic LIGO Voyager.

先进的LIGO探测器对聚结黑洞引力波的探测开启了引力波天文学的研究领域。将LIGO探测器的灵敏度提高几倍将增加引力波的数量和观测到的事件类型。未来的探测器，如计划于2021年推出的A+LIGO探测器，将受到与探测器光学中使用的镜面涂层相关的热噪声的限制。这项拟议的工作是斯坦福大学的Martin Fejer团队和佛罗里达大学的Hai-Ping Cheng团队合作开发具有较低热噪声的镜面涂层，以解决A+LIGO及更高级别的问题。二十多年来，斯坦福大学引力波研究计划一直致力于与LIGO科学合作(LSC)密切合作进行关键研究和缓解困难挑战，从而使引力波探测器成为可能。过去，斯坦福大学广泛参与了新型干涉仪组件和设计的开发、光学和降低光学和热噪声的详细研究，以及用于高级LIGO(ALIGO)的先进地震隔离系统。佛罗里达州的郑海平团队参与了计算材料模拟。为了支持LIGO，她模拟了非晶态薄膜的原子结构，并评估了与这些结构相关的机械损失，作为LSC开发低热噪声镜面涂层的更广泛努力的一部分。虽然Advanced LIGO现在已经具有足够的灵敏度来探测黑洞合并，但它的中带灵敏度将受到镜面涂层中机械耗散引起的热噪声的限制。斯坦福大学在LSC中发挥了领导作用，开发了实验方法来表征组成多层介质镜的非晶材料的光学、弹性和结构特性。佛罗里达州目前在LSC内进行计算材料建模工作。拟议的计划是一个协同团队，将这些技能集结合在一起，以解决一个关键问题，以满足A+LIGO的设计目标，开发出比目前最好的反射镜机械损失少2-4倍的反射镜。非晶态材料的机械损耗取决于其原子结构中微妙的、依赖于制备的特征。通过这里提出的电子衍射和X射线散射方法获得的这些结构特征的数据很难解释，对结构的分子动力学预测也是如此。存在使用建模来帮助解释数据和数据来帮助约束建模的方法，这导致了这里提出的团队安排。结构数据和弹性损失对材料成分和工艺条件的依赖关系的预测，将成为更广泛的LSC计划的主要贡献，该计划为A+LIGO开发反射镜，指导其他致力于这一问题的人通过可能的合成和表征实验。斯坦福大学的另一项长期工作是在亚ppm/cm级别的低光学损耗材料的光学表征方面，这可以追溯到在最初的LIGO测试质量中选择二氧化硅和蓝宝石。该小组最近开始使用为这些研究开发的干涉工具来表征单晶硅样品的低温损失，以评估它们作为计划中的低温LIGO旅行者号测试质量的适用性。

项目成果

Hidden structure in the medium-range order of amorphous zirconia-tantala films

非晶氧化锆-钽薄膜的中程隐藏结构

• DOI: 10.1103/physrevb.108.054103
• 发表时间: 2023
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Mishkin, Alec;Jiang, Jun;Zhang, Rui;Cheng, Hai-Ping;Prasai, Kiran;Bassiri, Riccardo;Fejer, Martin
• 通讯作者: Fejer, Martin

Amorphous Zirconia-doped Tantala modeling and simulations using explicit multi-element spectral neighbor analysis machine learning potentials (EME-SNAP)

使用显式多元素光谱邻域分析机器学习潜力 (EME-SNAP) 对非晶氧化锆掺杂 Tantala 进行建模和模拟

• DOI: 10.1103/physrevmaterials.7.045602
• 发表时间: 2023
• 期刊: Physical Review Materials
• 影响因子: 3.4
• 作者: Jiang, Jun;Li, Xiang-Guo;Mishkin, Alec S.;Zhang, Rui;Bassiri, Riccardo;Fry, James N.;Fejer, Martin M.;Cheng, Hai-Ping
• 通讯作者: Cheng, Hai-Ping

High Precision Detection of Change in Intermediate Range Order of Amorphous Zirconia-Doped Tantala Thin Films Due to Annealing

高精度检测非晶氧化锆掺杂钽薄膜因退火引起的中程序变化

• DOI: 10.1103/physrevlett.123.045501
• 发表时间: 2019
• 期刊: Physical Review Letters
• 影响因子: 8.6
• 作者: Prasai, K.;Jiang, J.;Mishkin, A.;Shyam, B.;Angelova, S.;Birney, R.;Drabold, D. A.;Fazio, M.;Gustafson, E. K.;Harry, G.
• 通讯作者: Harry, G.

Annealing‐Induced Changes in the Atomic Structure of Amorphous Silica, Germania, and Tantala Using Accelerated Molecular Dynamics

退火——利用加速分子动力学引起无定形二氧化硅、二氧化锗和钽原子结构的变化

• DOI: 10.1002/pssb.202000519
• 发表时间: 2021
• 期刊: physica status solidi (b
• 作者: Prasai, Kiran;Bassiri, Riccardo;Cheng, Hai-Ping;Fejer, Martin M.
• 通讯作者: Fejer, Martin M.

Analysis of two-level systems and mechanical loss in amorphous ZrO 2 -doped Ta 2 O 5 by non-cage-breaking and cage-breaking transitions

非晶ZrO 2 掺杂Ta 2 O 5 中非破笼和破笼转变的两能级系统和机械损失分析

• DOI: 10.1063/5.0046332
• 发表时间: 2021
• 期刊: The Journal of Chemical Physics
• 作者: Jiang, Jun;Mishkin, Alec S.;Prasai, Kiran;Zhang, Rui;Yazback, Maher;Bassiri, Riccardo;Fejer, Martin M.;Cheng, Hai-Ping
• 通讯作者: Cheng, Hai-Ping