Surface plasmon enhanced random lasing

This thesis presents the results of experimental and theoretical investigation of the effects of surface plasmon resonance on random laser systems. A numerical model is developed using the Finite Difference Time Domain algorithm to investigate the role of scattering from novel particles in a random laser system. Simulated results support the case for optical gain enhancement caused by surface plasmon resonance in silver nanoparticles. Several random laser devices are constructed and tested from the suspension of both silver and alumina nanoparticles in a laser dye. The use of silver scattering particles reduces the minimum spectral emission linewidth the input energy fluence threshold for lasing when compared to a random laser with alumina scattering particles. Random lasers are also constructed from the solid suspension of silver and alumina scattering nanoparticles in a solid photoresist. It is determined that the use of surface plasmon enhancement of local optical gain enables the construction of random lasers with superior performance to conventional random lasers with dielectric scatterers.