Continuous-wave stimulated emission and optical amplification in europium (III)-aluminum nanocluster-doped polymeric waveguide

The authors have demonstrated stimulated emission from polymer-based planar waveguide doped with Eu-Al nanoclusters under continuous-wave optical pumping. For the waveguide sample with a nanocluster concentration of 5.0 wt %, amplified spontaneous emission was observed in the spectra of the light decoupled from the waveguide edge under a pumping density of 0.16-1.55 W/cm(2). The optical gain coefficient was 0.92 mm(-1) when pumped at 1.55 W/cm(2). The well-suppressed concentration quenching and multiphonon quenching may cause the high-gain and low-threshold optical amplification. These results show that the Eu-Al nanocluster is a promising material for polymer-based solid-state lasers and waveguide-type optical amplifiers. (c) 2007 American Institute of Physics.