摘要
基于三包层长周期光纤光栅的耦合模型,研究了镀膜长周期光纤光栅的光栅参数和膜层厚度对长周期光纤光栅谐振波长的影响。研究发现,当长周期光纤光栅的纤芯半径、折射率和周期增大时,谐振波向长波方向漂移;当长周期光纤光栅的包层半径和折射率增大时,谐振波向短波方向漂移。不同折射率的膜层介质其所对应的最优厚度(Optimum Overlay Thickness,OOT)不同,薄膜介质的折射率越高,对应的最优厚度越小,敏感区域范围也较窄;不同包层模式对应的最优厚度具体位置区别不大,较高阶次包层模对应的谐振波长在敏感区域范围内漂移量较大。
Based on the model of triple-clad long period fiber grating(LPFG), the influence of structural parameters and overlay thickness on the resonant wavelength of LPFG is studied. It comes to the conclusion that when the radii, refractive index and grating period of fiber core increase, the resonance wavelengths shift towards longer wavelength; when the radii and refractive index of cladding increase, the resonance wavelengths shift towards shorter wavelength. Different refractive index of the overlay, different corresponding OOT it would have; the higher the refractive index of the overlayis, correspondingly, the smaller the OOT and the shorter the sensitive area would be. There is no big difference between the OOT of the different cladding modes, but the resonance wavelengths of the higher cladding modes have a targer shift in the sensitive area.
出处
《微型机与应用》
2015年第4期40-42,共3页
Microcomputer & Its Applications
基金
国家自然科学基金项目(61201109)
关键词
长周期光纤光栅
耦合模式
透射谱
long period fiber grating(LPFG)
coupled mode theory
transmission spectrum