Improved laser-induced deposition of silver nanoparticles on fiber end for surface-enhanced Raman scattering

This paper demonstrates an improved laser-induced deposition of silver nanoparticles method based on fiber surface micro-grating for surface-enhanced Raman scattering (SERS). The femtosecond (fs) laser ablation is used to create a roughened surface with micro-grating structures on the cleaved fiber end, which is beneficial for silver nanoparticles growth, and then the end of the fiber probe is immersed in a reaction solution for deposition of silver nanoparticles with a 785 nm exciting laser beam coupled into the fiber probe. The experiment results show that a larger number of silver nanoparticles have deposited on the roughed end using laser-induced method compared with the flat fiber end under the same induction conditions, leading to a better performance for the R6G molecules detection (about 32 times). Our rapid prepared fiber SERS probe provides a feasible method for real-time, high performance and remote measurement of the SERS signal in biochemical analysis.