Improved lasing characteristics of ZnO/organic-dye random laser

We investigate the random lasing characteristics of ZnO nanopowder suspended in methanol with the addition of organic-dye molecules. At a certain dye concentration, the random lasing intensity is enhanced, and the excitation threshold power is reduced. These improvements are explained by Förster-type resonant energy transfer from the dye-molecule donor to the ZnO-nanopowder acceptor.