GOALI: Nanostructured Sapphire Optical Fiber for Sensing in Harsh Environment

非技术描述：蓝宝石光纤在恶劣环境中进行传感的出色潜力早已得到认可，例如在先进的燃烧能源发电系统中遇到的高运行效率和低排放。蓝宝石光纤上缺乏用于低损耗光传输和光纤保护的可行包层，这仍然是现实世界应用的障碍。本项目旨在开发一种在蓝宝石光纤上具有高度有序的纳米空气通道的新型氧化铝包层，并通过在光纤上涂覆铝然后进行阳极氧化的策略来了解相关的工艺-结构-性能-性能相关性，用于逝去场化学传感和测量。该项目的成功有可能克服几十年来蓝宝石光纤包层的挑战，并为蓝宝石光纤技术的变革提供无数机会，特别是在石英光纤传感器不再适用的恶劣条件下的传感。该项目由史蒂文斯理工学院和FiberGuide Industries，Inc.合作实施。技术细节：无法制造稳定和高质量的可控光学特性覆层，严重阻碍了蓝宝石光纤传感器的设计和开发，用于许多应用，特别是在高温腐蚀性环境中。该项目旨在开发和评估蓝宝石光纤上的纳米结构氧化铝包层，用于逝去场化学传感和测量。主要目标是：(1)评估模场重叠和包层纳米结构之间的理论相关性，以指导包层制备；(2)确定铝涂层和阳极氧化的工艺参数窗口以及光纤导轨的放大；以及(3)使用逝去场激光吸收和表面增强拉曼散射作为检测手段，建立和理解包层纳米结构与燃烧环境中传感性能之间的相互作用。该项目具有变革性，因为它有可能解决蓝宝石光纤长期面临的包层瓶颈问题，并且由此产生的特种光纤很可能导致蓝宝石光纤技术的重大发展。此外，产业伙伴关系和国际合作作为研究活动的组成部分，极大地丰富了参与该项目的博士、本科生和高中学者的教育和研究培训经验。

NON-TECHNICAL DESCRIPTION: The excellent potential of sapphire optical fiber for sensing in harsh environments such as those encountered in advanced combustion-based energy generation systems for high operation efficiency and low emission has long been recognized. The lack of viable cladding on sapphire fiber for low-loss light transmission and fiber protection remains the roadblock to real-world applications. This project aims to develop a novel alumina cladding with highly organized nano-sized air channels on sapphire fiber and to understand the associated processing-structure-property-performance correlations for evanescent-field chemical sensing and measurements via a strategy of fiber coating with aluminum followed by its anodization. The success of the project has the potential to overcome the decades-old sapphire fiber cladding challenge as well as offer a myriad of opportunities to transformative sapphire fiber-optic technology especially for sensing under adverse conditions where silica fiber sensors are no longer suitable. This project is carried out in partnership between Stevens Institute of Technology and Fiberguide Industries, Inc. TECHNICAL DETAILS: The inability to fabricate stable and high-quality cladding of controlled optical properties severely hampers the design and development of sapphire fiber sensors for a host of applications, particularly in corrosive environments at high temperatures. This project aims to develop and evaluate nanostructured alumina cladding on sapphire fiber for evanescent-field chemical sensing and measurements. The main objectives are: (1) evaluation of the theoretical correlation between mode-field overlap and cladding nanostructure to guide cladding fabrication; (2) determination of the window of processing parameters for aluminum coating and anodization as well as scale-up at Fiberguide; and (3) establishment and understanding of the interplay between the cladding nanostructure and sensing performance in combustion environment using evanescent-field laser absorption and surface-enhanced Raman scattering as the detection modalities. This project is transformative in that it has the potential to resolve the bottle-neck cladding problem long-faced by sapphire fiber and that the resultant specialty optical fiber may well lead to significant development of sapphire fiber-optic technology. Furthermore, industrial partnership and international collaboration as an integral part of the research activities greatly enriches the educational and research training experiences of the doctoral, undergraduate and high-school scholars participating in this project.