微纳Taper光纤干涉传感器的折射率测量理论研究

利用微纳taper光纤干涉方程和微纳光纤传输模式函数关系,建立了微纳taper光纤干涉波长随环境折射率变化的数学模型,指出微纳taper光纤干涉波长的响应规律由基模高阶模有效折射率差、色散因子和环境折射率3个因素所决定.详细研究了微纳taper光纤传感器的灵敏度变化规律,结果表明,传感器的灵敏度随光纤半径变小而急速增大,并随环境折射率的增大而非线性增加,而且探测波长越长,其灵敏度越大.

Theoretical Study of the Refractive Index Measurement Based on Tapered Micro/Nano Fiber Interference Sensor

Based on the tapered micro-nano fiber interference equation and micro-nano fiber transmission mode function relationship,this paper establishes a mathematical model of the tapered micro-nano interference wavelength with environmental refractive index.And it points out the response law of the interference wavelength of the tapered micro-nano fiber is determined by three factors:the effective refractive index difference of the fundamental mode high-order mode,the dispersion factor and the environmental refractive index change.This paper studies the sensitivity variation law of the micro-nano taper fiber sensor.The results show that the sensitivity increases sharply with the decrease of the fiber radius and increases nonlinearly with environmental refractive index larger.Furthermore,the longer the detection wavelength is,the greater the sensitivity is.