Collaborative Research: NSF/ENG/ECCS-BSF: Complex liquid droplet structures as new optical and optomechanical materials

合作研究：NSF/ENG/ECCS-BSF：复杂液滴结构作为新型光学和光机械材料

• 批准号: 1711798
• 负责人: Jie Xu
• 金额: $ 14.81万
• 依托单位: University of Illinois at Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1711798&HistoricalAwards=false
• 关键词: Collaborative; Research; NSF; ENG; ECCS

Confining light to region of hundreds or even tens of micrometers in high-quality optical microresonators, one can achieve a significant concentration of electromagnetic energy. The confined light becomes much more sensitive to environmental changes, exerts an amplified mechanical force, and can generate significant nonlinear effects even at small light intensities. For this reason, optical microresonators are being actively studied in the context of optical cooling or amplification of mechanical motion, for precision metrology, lasing, ultrasensitive biosensing and other areas. Confinement of light is usually achieved using solid materials, but this project proposes to achieve it using liquid microstructures. The transition to liquid droplet creates significant challenges, but also opens up new opportunities. Firstly, mechanical softness of droplets makes them more receptive than solid materials to the light-induced forces resulting in many orders of magnitude larger mechanical responses and hence increased efficiency of optical cooling or heating. Secondly, liquid droplets allow access to the resonator's interior regions. Because electromagnetic field is orders of magnitude larger inside than outside of the resonator, one can expect the corresponding increase in sensitivity of biosensors based on droplet resonators by several orders of magnitude. Thirdly, use of liquid droplets allows realizing a novel class of photonic molecules with extra strong optical bonds based on droplet-in-droplet structures, in which one or more smaller droplets are encapsulated in a larger droplet. Overall, the objective of this project is to demonstrate the transformative potential of liquid droplet resonators in the fields of optical cooling, lasing, sensing and metrology. The interdisciplinary nature of the project, which includes physicists, and electrical and mechanical engineers, will ensure that graduate and undergraduate students will be exposed to the culture and methodology of different disciplines. In addition, the project will build connections between American and Israeli researchers and students and strengthen the collaboration between American universities participating in the project and Technion, Israel's premiere engineering school. The support for this project is provided within the collaborative NSF-BSF (Binational US-IL Science Foundation) program with participation of the Israel team financed by BSF.This project merges the fields of microfluidics and optical whispering-gallery- mode resonators by proposing the study of the optical and optomechanical properties of novel photonic structures composed of fluid droplets. The mechanical softness of liquid droplets combined with their versatility and tunability will allow the principal investigators to study novel optical and optomechanical effects such as optical cooling of capillary waves, topological energy transfer in the vicinity of exceptional points, and others. The international multidisciplinary team formed for this project will exploit state-of-the-art microfluidic technologies to fabricate different structures of droplets, with each droplet serving as a high-quality photonic resonator. Numerical simulation and theoretical models will be developed to understand the physics associated with the novel structures developed in the project. Experimentalists working on the project will carry out optical characterization of the proposed structures and develop in-depth understanding of their novel optical and optomechanical effects. This research will advance the field of optofluidics by applying state-of-the-art 3D printing technologies to the fabrication of novel microfluidic devices and generation of complex structures of microdroplets. Study of novel photonic structures with unique properties will also open new directions in the field of optical whispering-gallery-mode resonators. The general field of computational electrodynamics will also benefit from this work by taking the T-matrix formalism well outside its nominal domain and applying it to the modes of optically coupled complex structures of liquid droplets.

将光线限制在高质量光学微孔子中数百甚至数十微米的区域，可以达到明显的电磁能。狭窄的光对环境变化变得更加敏感，施加放大的机械力，即使在小光强度下，也会产生明显的非线性效应。因此，在光学冷却或机械运动放大的背景下，正在积极研究光学微孔子，以进行精确测量，激光，超敏感生物传感和其他区域。通常使用固体材料来实现光的限制，但是该项目建议使用液体微观结构实现它。向液滴的过渡带来了重大挑战，但也开辟了新的机会。首先，液滴的机械柔软度使它们比固体材料更容易受到光诱导的力，从而导致许多数量级的机械响应更大，从而提高了光学冷却或加热的效率。其次，液滴允许进入谐振器的内部区域。由于电磁场比谐振器外部大的数量级高，因此人们可以期望基于液滴谐振器的生物传感器的灵敏度相应提高，几个数量级。第三，使用液滴的使用允许实现一类新型的光子分子，这些光子分子具有基于滴水的液滴结构，具有额外的强光键，其中将一个或多个较小的液滴封装在较大的液滴中。总体而言，该项目的目的是证明液滴谐振器在光学冷却，激光，传感和计量学领域的变化潜力。该项目的跨学科性质，包括物理学家，电气和机械工程师，将确保研究生和本科生将受到不同学科的文化和方法的影响。此外，该项目将建立美国和以色列研究人员与学生之间的联系，并加强参加该项目和技术的美国大学的合作，这是以色列首屈一指的工程学校。对该项目的支持是在由BSF资助的以色列团队参与的协作NSF-BSF（Binational US-IL科学基金会）中提供的。该项目通过提出对光学和光学机械性能的研究的研究来融合微流体和光向窃窃私语模式谐振器的领域。液滴的机械柔软性与它们的多功能性和可调性相结合，将使主要研究人员能够研究新颖的光学和光学机械效应，例如毛细管波的光学冷却，特殊点附近的拓扑能量转移等等。为该项目组成的国际多学科团队将利用最先进的微流体技术来制造不同的液滴结构，每个液滴都充当高质量的光子谐振器。将开发数值模拟和理论模型，以了解与项目中开发的新结构相关的物理学。从事该项目的实验人员将对所提出的结构进行光学表征，并深入了解其新型的光学机械效应。这项研究将通过将最先进的3D打印技术应用于新型微流体设备的制造和微副子的复杂结构的产生，从而推动光荧光学的领域。对具有独特特性的新型光子结构的研究还将在光学耳语 - 助和模式谐振器领域开放新方向。计算电动力学的一般领域也将通过将T-Matrix形式主义远远超出其名义域并将其应用于液滴的光学耦合复杂结构的模式，从而从这项工作中受益。

项目成果

Pressure of a viscous droplet squeezing through a short circular constriction: An analytical model

• DOI: 10.1063/1.5045495
• 发表时间: 2018-10-01
• 期刊: PHYSICS OF FLUIDS
• 影响因子: 4.6
• 作者: Zhang, Zhifeng;Drapaca, Corina;Xu, Jie
• 通讯作者: Xu, Jie