片上荧光薄膜气体传感融合了光学芯片小型化与荧光探针高灵敏度特性的优势，具备广阔的应用前景。当前主流芯片多采用片上氮化硅直波导结构，存在直波导倏逝场穿透深度有限、荧光收集效率低等问题，造成片上荧光信号信噪比差、输出光谱保真度不足。同时，器件检测性能易受激发功率波动与环境因素干扰，单一检测模式难以满足复杂场景下气体高灵敏、高选择性的检测需求。
Recently, the scientific research team of the Shanghai Institute of Microsystems and Information Technology, Chinese Academy of Sciences, developed a hybrid integrated gas sensing silicon photonic chip. By fusing a fluorescent sensing film with an optical microring resonator, the chip achieves chemical-optical dual-mode collaborative signal amplification, breaking through the performance bottlenecks of traditional fluorescent gas sensors in terms of sensitivity and selectivity.
团队提出基于硅基光子集成芯片的微环谐振腔增强方案，利用微环谐振腔优异的光谱调制特性，将宽谱荧光发射转化为离散的高品质因子谐振峰，同步提升了输出信号的信噪比与光谱保真度。团队进一步The fluorescent probe material is mixed and integrated with the microring area through a solution processing method. Electron microscopy characterization and spectral test results prove that this hybrid integration method can effectively ensure that the microring structure maintains a high quality factor after depositing the sensing film, thereby effectively modulating the emission spectrum of the fluorescent film.
This dual-mode synergy mechanism significantly improves the sensing performance, and the actual measured gas detection limit is as low as 1.25ppb. The two independent signals of fluorescence intensity and resonance wavelength can support each other, and the identification accuracy is improved through multi-dimensional criteria, effectively solving the problem of difficulty in distinguishing gases with similar fluorescence quenching behavior. The study also established a theoretical model to illustrate the synergistic mechanism, and verified the universality of the method on a variety of fluorescent probes.
相关研究成果发表在《激光与光子学评论》（Laser & Photonics Reviews）上。研究工作得到国家自然科学基金委员会、中国科学院的支持。
单模式与双模协同传感机制对比示意图
Si3N4Hybrid integration method and performance characterization of microring photonic chip and fluorescent probe
Source: https://www.cas.cn/syky/202608/t20260827_5119139.shtml