Dingke Zhang, Yanping Wang, Dongge Ma
Jun 19, 2008
Citations
0
Influential Citations
6
Citations
Journal
Journal of Applied Physics
Abstract
Random multimode lasers are achieved in 4-(dicyanomethylene)-2-tert-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) doped polystyrene thin films by introducing silicon dioxide (SiO2) nanoparticles as scatterers. The devices emit a resonance multimode peak at a center wavelength of 640 nm with a mode linewidth less than 0.87 nm. The threshold excitation intensity is as low as 0.25 mJ pulse−1 cm−2. It can be seen that the microscopic random resonance cavities can be formed by multiple scattering of SiO2 nanoparticles. The transport mean free length is estimated to be about 156 μm. The demonstration of random organic lasers opens up the possibility of using scattering as an alternative source of coherent light emission.