飞秒写制长周期光纤光栅的液体浓度测量实验研究  

Solution concentration sensing characteristics of LPFG written by femtosecond laser pulses

作　　者：张玲[1] 苗飞[1] 隋青美[1] 冯德军[2] 刘汉平[3] 刘辉兰[3] 

机构地区：[1]山东大学控制科学与工程学院,山东济南250061 [2]山东大学信息科学与工程学院,山东济南250100 [3]德州学院物理系,山东德州253023

出　　处：《光电子．激光》2012年第5期897-901,共5页Journal of Optoelectronics·Laser

基　　金：山东省自然科学基金(ZR2011AL005);山东省自然科学基金(ZR2010FM001);山东大学自主创新基金(2010TS014);山东省高校科研发展计划(J10LA54)资助项目

摘　　要：利用逐点写入法在去涂敷层的普通单模通信光纤中直接写入了长周期光纤光栅(LPFG),实验获得的LPFG在C波段的谐振波长1 538.8nm,衰减强度达10.63dB。其氯化钠和蔗糖溶液浓度传感特性实验表明,随着盐溶液浓度的增大,LPFG的谐振波长向左线性漂移,盐浓度每增加1%,波长向左漂移约0.05nm;随着糖溶液浓度从0%增大为50%,LPFG的谐振波长向左非线性漂移量高达约8nm。实验结果表明:飞秒激光逐点写入法操作简单,容易控制诱导的周期性折射率微扰在纤芯和或包层的位置,从而制备出对低浓度液体敏感的LPFG化学传感器;同时飞秒激光写制的LPFG具有较高的外界环境灵敏度,有望用在化学浓度传感中。Long-period fiber gratings（LPFGs） are successfully inscribed in the coating-removed single mode fiber by point-by-point method.The resonant wavelength in the C band is 1 538.8 nm and its attenuation depth is above 10 dB.Further solution concentration sensing experiments of sodium chloride and sucrose show that the resonant wavelength drifts linearly to the left with the increasing of solution concentration of sodium chloride;the wavelength shift is about 0.05 nm for the salt concentration increasing by 1%,and the wavelength drifts nonlinearly to the left by about 8 nm when the sucrose concentration increases from 0% to 50%.The experimental results show that the point-by-point inscription method using femtosecond laser is simple and flexible,and it is easy to control the location of periodic refractive index perturbation in fiber core or/and cladding,so the LPFG chemical sensors which are more sensitive to low-concentration solutions can be fabricated.In addition,the LPFG written by femtosecond laser pulses has high sensitivity to the external refractive index and is expected to be used in the chemical concentration sensing.

关 键 词：长周期光纤光栅(LPFG) 飞秒激光 折射率测量 液体浓度测量 

分 类 号：TN253[电子电信—物理电子学]