In this letter, we demonstrate a high-sensitivity flow rate sensor which is packaged using a stable and convenient method. The sensor is based on an optofluidic microbottle resonator (OFMBR), which serves as a promising platform for fluid sensing due to its ultrahigh quality factor and inherent microfluidic channel. The coupling system is packaged using a modified method, and the sensor’s stability is verified using phosphate buffered saline at different flow rates. According to the Bernoulli effect of fluid, the dynamic change of velocity in OFMBR can be detected via wavelength shift mechanism of whispering galley mode. Both the simulated and experimental results show that sensitivity can be enhanced for a given wall thickness by exploiting higher order radial modes of the OFMBR. The maximum sensitivity of 0.079 pm/( $\mu \text{L}$ /min) within the range of 0- $200~\mu \text{L}$ /min is achieved in the experiment. This sensor provides an optional method for fluid detection with high sensitivity and stability.

中文翻译：

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封装微瓶谐振器的高阶模式可实现高灵敏度流量传感器

在这封信中，我们演示了使用稳定方便的方法包装的高灵敏度流量传感器。该传感器基于光流体微瓶谐振器（OFMBR），由于其超高品质因数和固有的微流体通道，该传感器可作为有前途的流体传感平台。耦合系统使用改进的方法进行包装，并且使用磷酸盐缓冲盐水以不同的流速验证了传感器的稳定性。根据流体的伯努利效应，可以通过耳语厨房模式的波长偏移机制来检测OFMBR中速度的动态变化。仿真结果和实验结果均表明，通过利用OFMBR的高阶径向模式，可以提高给定壁厚的灵敏度。最大灵敏度为0.079 pm /（ $ \ mu \ text {L} $ / min），范围为0- $ 200〜\ mu \ text {L} $ / min在实验中达到。该传感器提供了一种可选的方法，可实现高灵敏度和稳定性的流体检测。