Plasmonic random lasing in polymer fiber.

A random fiber laser is achieved based on the plasmonic feedback mechanism, which is constructed by first siphoning the polymer solution doped with silver nanoparticles into a 300-μm capillary tube and then evaporating the solvent. Strong amplification of the radiation can be obtained by employing the variable gain region, the fiber waveguide scheme and three-dimensional plasmonic feedback provided by the silver nanoparticles. Low-threshold directional random lasing is observed in the polymer fiber. This simple and straightforward approach facilitates the investigation of plasmonic random fiber lasers.