Optically pumped blue organic semiconductor lasers

Lasing at 460, 485, and 510 nm is demonstrated in optically pumped, vacuum-deposited amorphous thin films of a carbazole derivative doped with Coumarin 47, perylene, and Coumarin 30, respectively. Efficient, nonradiative Forster energy transfer between host and dopant organic molecules results in low lasing thresholds (5 μJ/cm2), high differential quantum efficiencies (15%), high peak output powers (20 W), and long operational lifetimes (>105 pulses at 100 times the threshold power).