Lane S, Marsiglio F, Zhi Y, Meldrum A
Appl Opt. 2015 Feb 20;54(6):1331-40. doi: 10.1364/AO.54.001331.
Fluorescent-core microcapillaries (FCMs) present a robust basis for the application of optical whispering gallery modes toward refractometric sensing. An important question concerns whether these devices can be rendered insensitive to local temperature fluctuations, which may otherwise limit their refractometric detection limits, mainly as a result of thermorefractive effects. Here, we first use a standard cylindrical cavity formalism to develop the refractometric and thermally limited detection limits for the FCM structure. We then measure the thermal response of a real device with different analytes in the channel and compare the result to the theory. Good stability against temperature fluctuations was obtained for an ethanol solvent, with a near-zero observed thermal shift for the transverse magnetic modes. Similarly good results could in principle be obtained for any other solvent (e.g., water), if the thickness of the fluorescent layer can be sufficiently well controlled.
荧光芯微毛细管（FCM）为将光学回音壁模式应用于折射传感提供了坚实的基础。一个重要的问题是这些器件能否对局部温度波动不敏感，否则局部温度波动可能会限制其折射检测极限，主要是由于热折射效应。在这里，我们首先使用标准的圆柱腔形式来推导FCM结构的折射和热限检测极限。然后，我们测量了通道中含有不同分析物的实际器件的热响应，并将结果与理论进行比较。对于乙醇溶剂，获得了对温度波动的良好稳定性，横向磁模式的热位移几乎为零。原则上，如果荧光层的厚度能够得到充分良好的控制，对于任何其他溶剂（如水）也可以获得类似的良好结果。
