An Au NP doped buffer layer in a slab waveguide for enhancement of organic amplified spontaneous emission

Abstract

Gold nanoparticles are doped into a low refractive buffer layer (PMMA) to promote the amplified spontaneous emission (ASE) performance of a red-emissive polymer (MEH-PPV) in a slab waveguide device structure: Quartz/PMMA/MEH-PPV/Air. This facile device structure with the PMMA buffer layer results in a significant ∼12 fold enhancement of the ASE intensity and lowers the gain threshold by ∼40%. Remarkably, the enhanced ASE intensity beyond the gain threshold is much stronger than the control device without gold nanoparticles. Our results show that the surface plasmon resonance of gold nanoparticles in the slab waveguide structure can effectively increase the density of excited states (gain) and decrease energy losses (loss) and can be easily fabricated by solution processing methods. Our investigations indicate that buffer layer modification with metal nanoparticles exhibits huge potential for practical applications in the performance enhancement of organic lasers.