Energy-Transfer Dye Laser in SolGel Silica

Coumarin 460 transfers radiative energy to disodium fluorescein when solgel silica is doped with the dyes, producing disodium fluorescein lasing in superradiant mode at a 3.3% peak efficiency under low-energy transverse pumping by a 1.5-mJ N(2) laser, with disodium fluorescein being present at a concentration below its lasing threshold value.