In Situ Synthesis Of Nanostructure On Distal Facet Of Fiber By Photochemistry Reaction

Optical fiber, because of its excellent performance and outstanding ability of anti-electromagnetic radiation and electromagnetic sensing technology, is widely applied in the field. At this stage, FBG sensors, near field optical fiber probe, fiber optic chemical sensors and fiber optic biosensor sensing field all have important positions. The performance of the sensor depends mainly on its sensing element-fiber optic probes. Preparation technology of fiber optic probe directly determines its sensitivity and durability, thereby affecting the performance and prospects of fiber optic sensors. The fiber optic probe preparation techniques are complexing, time-consuming and unstable during repetitive production, this paper aims at achieving rapid preparation technology fiber optic probe through the top Micro-Fiber nanostructures in situ photochemical preparation technology. This article have two aspects:1) using laser-induced deposition of nano-silver in the single-mode fiber and fiber beam deposition of silver nanoparticles to achieve a rapid controllable preparation of nano silver fiber probe; 2) using laser-induced free radicals polymerization to prepare a near-field optics which are used in the field of polymer fiber optic probe to obtain a higher resolution near-field optics. Specific work is as follows:Firstly, by using laser-induced rapid reduction method in the top end face of 7x7 of single-mode optical fiber and the optical fiber bundle, we can deposit silver nanoparticles. At the same time by scanning electron microscopy (SEM) to observe the deposition morphology of silver nanoparticles under different laser intensity and induction time, which confirms we can generate a lot of size distribution of silver nanoparticles when the laser intensity is 25 microwatts induction time to reach 0.5 s. In addition, by monitoring the transmittance of the fiber end face of 532nm laser deposition, we can continuously percept the deposited amount of silver nanoparticlesSecondly, different length dimensions of the polymer structure of the probes can be produced directly in a single-mode optical fiber end face by using laser-induced radical polymerization method. And by using SEM to observe the fiber end face of high growth dimer structures under different conditions of the laser intensity and the induction time, we find out the optimal experimental conditions for preparing such a polymer fiber optic probe (laser intensity 250nw-1000nw, induction time 2s). Finally, excellent near-field optical resolution can be get when using such polymer optical fiber probe to observe submicron particles near-field optical.