Fibre nanowire sensors

最近，许多人致力于开发用于化学和生物传感的紧凑型设备，特别是环境、航空航天和安全应用。双重目标是在提高灵敏度的同时减小设备的尺寸。在这里，我们建议将新兴的光学纳米线技术应用于这一任务，该技术可以将器件尺寸从大约10厘米减小到亚毫米范围，并具有前所未有的探测器灵敏度。光学纳米线是由标准光纤通过高温拉伸工艺制成的。它们的直径为亚微米，便于弯曲和操纵，但机械性能相对较强。在光学纳米线中传播的光远远超出材料延伸到空气中，从而为传感应用提供与环境的强烈相互作用。最后，光可以很容易地进入和离开纳米线，这对紧凑和节能的设备很重要。在这项提议中，我们的目标是进一步发展这项新兴技术，以降低传输损耗，将纳米线嵌入结构材料中以增强稳健性，并建立自耦合干涉仪和谐振器。最后，我们将首次将光学纳米线应用于两个特定的设备：a)我们将用光学纳米线制造紧凑的高灵敏度Sagnac干涉仪。Sagnac干涉仪通常用作飞机上的旋转传感器。我们的新设备将明显更小，同时至少提供相同的灵敏度。b)我们将利用部分嵌入的纳米线谐振器开发一种毫米尺寸的气体传感器。高谐振腔质量和光与周围气体的大相互作用将通过腔振铃光谱提供更高的灵敏度。

Much effort has been devoted recently to developing compact devices for chemical and biological sensing, in particular for environmental, aerospace and security applications. The double goal is to increase the sensitivity while simultaneously reducing the size of the devices. Here we propose to apply the emerging technology of optical nanowires to this task, which could reduce device sizes from approximately ten centimetres to the sub-millimetre range combined with unprecedented detector sensitivity.Optical nanowires are fabricated from standard optical fibres by a high-temperature drawing process. They have submicron diameters, which allows for easy bending and manipulation, yet they remain relatively strong mechanically. Light propagating in an optical nanowire extends well beyond the material into air, thus providing strong interaction with the environment for sensing applications. Finally, light can easily be coupled into and out of a nanowire, which is important for compact and energy-efficient devices.In this proposal we aim to further develop this emerging technology to reduce transmission losses, to embed nanowires into structural materials for enhanced robustness, and to build self-coupled interferometers and resonators. Finally, we will, for the first time, apply optical nanowires in two specific devices:a) We will manufacture compact high-sensitivity Sagnac interferometers from optical nanowires. Sagnac interferometers are routinely used on aircrafts as rotation sensors. Our new device will be significantly smaller, while providing at least the same sensitivity.b) We will develop a millimetre-sized gas sensor from a partially embedded nanowire resonator. High resonator quality and large interaction of the light with surrounding gas will provide enhanced sensitivity by cavity ringdown spectroscopy.