采用拍频检测的内嵌型微环传感器研究

Nested Microring Resonator Sensor Using Beat Frequency Detection

提出了一种内嵌型微环传感结构。利用内嵌型结构产生的高Q值滤波峰,采用拍频检测技术,可以实现高灵敏度传感器。采用传输矩阵法分析了内嵌微环半径对滤波峰位置及相邻滤波峰之间关系的影响。内嵌微环的滤波峰产生了分裂,其波长间距很小,且随折射率变化波长间距也会变化。利用该器件构建了拍频检测系统,并对该器件进行传感分析。仿真结果表明,该结构的传感灵敏度为1×10-4折射率单位(RIU),其频率偏移为4 MHz/1×10-4RIU。

A nested microring resonator is presented and its application for beat frequency sensing is demonstrated. The theoretical analysis of this structure has been obtained by transfer matrix method. By changing bending radius of the inner ring,the relations between it and resonance wavelength spacing have been theoretically analyzed. The sim-ulation results show that the resonator frequency of inner microring splits to two peaks and the frequency interval of this two peaks is very narrow which show this structure can be used as a sensor detector in beat frequency sensing system. Therefore,by changing the refractive index,the output spectrum response is analyzed in optical and micro-wave regime. For this beat frequency system,the sensitivity is 1×10^-4 refractive index unit（RIU）and the frequency shift is 4 MHz/1×10^-4 RIU.