Abstract

We report the operation and characterization of two different three-photon pumped anti-Stokes emission in Random Lasers (RL) in different materials. Using a special dye with a high three-photon cross-section and TiO₂ nanoparticles (250 nm diameter), optimized upconverted emission was obtained for particle densities of ~2 × 10⁹/cm³, pumped by a 1350nm femtosecond laser. On the other hand, by exploiting the important and versatile ZnO semiconductor on a ZnO-on-Si nanostructured film platform, upconverted RL emission centered at ~390nm was obtained by three-photon excitation at 802nm. We demonstrate characteristic random laser features, as the presence of an intensity threshold and a linewidth narrowing.

© 2014 Optical Society of America