基于氧化石墨烯的长周期光纤光栅的全光控制

All optical control of long period fiber grating based on graphene oxide

实验验证了一种通过将氧化石墨烯分散液沉积在长周期光纤光栅的全光控制的相关研究。通过外加的垂直泵浦光的作用,氧化石墨烯吸收泵浦光产生热量,改变长周期光纤光栅的包层模式的相位差,由于热膨胀的作用改变了氧化石墨烯所覆盖部分的光栅周期,使得谐振谱发生了移动,其最大调制深度可达10.6 dB,谐振谱最大可红移12.8 nm。通过实验发现,沉积相同浓度氧化石墨烯分散液的次数影响实验结果,通过在相同光栅的相同位置分别沉积三次,发现沉积三次可以在光纤表面获得更加均匀的氧化石墨烯膜,进行了时间响应的测试,其中沉积三次后的长周期光纤光栅的响应速度可达0.61 ms,沉积多次氧化石墨烯分散液可以在光纤表面沉积得更加平整均匀,从而获得更大的导热性能。

A kind of all-optical control method based on the deposition of graphene oxide dispersion in long period fiber grating is proposed and experimentally validated.Pumped by an external vertical light,graphene oxide generates heat and changes the phase difference of the cladding mode of long-period fiber grating.Due to the effect of thermal expansion,the grating period of the part covered by graphene oxide is changed,which makes the resonance spectrum shift.The maximum modulation depth can reach 10.6 dB,and the maximum resonance spectrum can be redshifted by 12.8 nm.It is found that the number of times to deposit graphene oxide dispersion with the same concentration influences the experimental results.By depositing graphene oxide dispersion at the same position of the same grating once and three times respectively,it is found that the more uniform graphene oxide film can be obtained on the surface of optical fiber by three times of deposition,which enhances the interaction between light and graphene oxide,and has higher modulation efficiency and tuning efficiency.Finally,the time response test is carried out,and the response speed of the long period fiber grating after three times of deposition can reach 0.61 ms.It is found that the graphene oxide dispersion can be deposited more evenly on the surface of the optical fiber,thus obtaining greater thermal conductivity.