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: 1707866
• 负责人: Martin Fejer
• 金额: $ 135万
• 依托单位: Stanford University
• 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 2020-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1707866&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探测器从聚合黑洞中对重力波的检测已引发了引力波天文学的领域。多次提高Ligo检测器的灵敏度将增加引力波的数量和观察到的事件类型。未来的探测器，例如计划于2021年的A+ LIGO探测器，将受到与检测器光学镜像相关的热噪声的限制。拟议中的工作是斯坦福大学马丁·费耶尔（Martin Fejer）小组与佛罗里达大学的Hai-ping Cheng小组之间的合作努力，以开发具有较低热噪声的镜像涂料，以解决A+ Ligo及其他地区的这个问题。斯坦福引力波研究计划已有二十多年的研究参与了研究，以通过与Ligo Science合作（LSC）紧密合作以进行重要的研究并减轻困难挑战，从而实现了引力波检测。过去，斯坦福大学为新的干涉仪组件和设计的发展，对光学和缓解光学和热噪声的详细研究以及高级Ligo（Aligo）中使用的先进的地震隔离系统的详细研究做出了广泛的贡献。佛罗里达州的Hai-Ping Cheng小组参与了计算材料模拟。为了支持Ligo，她对无定形膜的原子结构进行了建模，并评估了与这些结构相关的机械损失，这是开发低热量噪声镜面涂层的更广泛努力的一部分。虽然先进的Ligo现在已经具有足够的灵敏度来检测黑洞融合，但其中带灵敏度将受到镜面涂层机械耗散产生的热噪声的限制。斯坦福大学在LSC中在开发实验方法中发挥了领导作用，以表征组成多层介电镜的无定形材料的光学，弹性和结构特性。佛罗里达州在LSC中进行了当前的计算材料建模工作。该计划是一个协同的组合，旨在将这些技能组合结合起来，以解决一个关键问题，以实现A+ Ligo的设计目标，开发了镜子的机械损失比当前最佳的镜子少的2-4倍。无定形材料中的机械损失取决于其原子结构中的微妙，制备依赖性特征。有关通过电子衍射和X射线散射方法获得的这些结构特征的数据，解释很具有挑战性，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以帮助限制建模的方法，这导致了此处提出的组合安排。弹性损失对材料组成和过程条件的依赖性的结构数据和预测将成为更广泛的LSC计划的主要贡献者，以开发A+ Ligo的镜像，从而通过可能的合成和表征实验的灌木丛来指导其他问题。斯坦福大学的另一项长期努力是在子ppm/cm水平上对低光损失材料的光学表征，可以追溯到二氧化硅和蓝宝石之间的初始LIGO测试质量的选择。该小组最近开始使用为这些研究开发的干涉测量工具来表征单晶硅样品中的低温损失，以评估其适合性作为计划中的低温Ligo Voyager中的测试量。

项目成果

Modifications of ion beam sputtered tantala thin films by secondary argon and oxygen bombardment

二次氩氧轰击离子束溅射氧化钽薄膜的改性

• DOI: 10.1364/ao.59.00a150
• 发表时间: 2020
• 期刊: Applied Optics
• 影响因子: 1.9
• 作者: Yang, Le;Randel, Emmett;Vajente, Gabriele;Ananyeva, Alena;Gustafson, Eric;Markosyan, Ashot;Bassiri, Riccardo;Fejer, Martin;Menoni, Carmen
• 通讯作者: Menoni, Carmen

Effect of elevated substrate temperature deposition on the mechanical losses in tantala thin film coatings

高温沉积对氧化钽薄膜涂层机械损失的影响

• DOI: 10.1088/1361-6382/aaad7c
• 发表时间: 2018
• 期刊: Classical and Quantum Gravity
• 影响因子: 3.5
• 作者: Vajente, G;Birney, R;Ananyeva, A;Angelova, S;Asselin, R;Baloukas, B;Bassiri, R;Billingsley, G;Fejer, M M;Gibson, D
• 通讯作者: Gibson, D

Cryogenic mechanical loss of a single-crystalline GaP coating layer for precision measurement applications

用于精密测量应用的单晶 GaP 涂层的低温机械损失

• DOI: 10.1103/physrevd.95.042004
• 发表时间: 2017
• 期刊: Physical Review D
• 影响因子: 5
• 作者: Murray, Peter G.;Martin, Iain W.;Craig, Kieran;Hough, James;Rowan, Sheila;Bassiri, Riccardo;Fejer, Martin M.;Harris, James S.;Lantz, Brian T.;Lin, Angie C.
• 通讯作者: Lin, Angie C.

Bulk and shear mechanical loss of titania-doped tantala

二氧化钛掺杂钽的体积和剪切机械损失

• DOI: 10.1016/j.physleta.2017.08.007
• 发表时间: 2018
• 期刊: Physics Letters A
• 影响因子: 2.6
• 作者: Abernathy, Matthew;Harry, Gregory;Newport, Jonathan;Fair, Hannah;Kinley-Hanlon, Maya;Hickey, Samuel;Jiffar, Isaac;Gretarsson, Andri;Penn, Steve;Bassiri, Riccardo
• 通讯作者: Bassiri, Riccardo

Influence of deposition parameters on the optical absorption of amorphous silicon thin films

沉积参数对非晶硅薄膜光吸收的影响

• DOI: 10.1103/physrevresearch.2.033308
• 发表时间: 2020
• 期刊: Physical Review Research
• 影响因子: 4.2
• 作者: Terkowski, Lukas;Martin, Iain W.;Axmann, Daniel;Behrendsen, Malte;Pein, Felix;Bell, Angus;Schnabel, Roman;Bassiri, Riccardo;Fejer, Martin M.;Hough, Jim
• 通讯作者: Hough, Jim