超灵敏微力传感器对研究光与物质相互作用，探索生命科学关键问题，研制新型微纳器件具有重要意义。常用的原子力显微镜与磁镊的力学反馈机制复杂；光镊系统使用的激光强度大，易造成生物分子和细胞的损伤。如何基于新原理、新材料，构建结构简单、灵敏度高、工作范围宽、检测通量高的超灵敏微力传感器成为科学研究的一个迫切需求。本课题拟采用微纳光纤构建一种自带光学感知功能的悬臂梁传感器，微纳光纤既是悬臂梁的主体，又是信号光的载体，该结构不仅可以显著降低系统复杂性，还能大幅提高传感器的灵敏度和灵活性。本课题提出了探针形微纳光纤悬臂梁和具有纳流控通道的U形微纳光纤悬臂梁两种传感结构，基于微纳光纤导波模式转变原理，通过实时探测微纳光纤输出光强或悬臂梁振动频率的变化，开展单分子力谱和高通量单个纳米颗粒的特性研究。通过本项目研究，研制一种新型超灵敏微纳光纤传感器，推动光学传感技术的进步，促进生物、物理等学科的发展。

Ultrasensitive microforce sensor is the key to the success of understanding the fundamental processes of momentum exchange between light and matter, biology, and micro/nano devices. However, it is still a great challenge to construct ultrasensitive microforce sensors with large dynamic range, high throughput, and wide application potential by developing new transduction mechanisms and structural designs. Different from atomic force microscopy or micro/nanomechanical resonator which detects the microbending of cantilever by recording the reflected light from the top of the cantilever, we propose a novel concept by using micro/nanofiber (MNF) as cantilever and waveguide. In this case, the bending of the MNF can be detected by monitoring the transmission of the MNF or the shift of the resonance. Two types of sensors, named probe-shape MNF cantilever and U-shape MNF cantilever, are designed for single molecule force spectroscopy and high throughput weighting single nanoparticles. The outcome of this research will be a series of optical sensors which can boost the development of optical sensor, promote the study in the fundamentals of physics and biology.