STUDY OF LASING ACTION BASED ON FORSTER ENERGY-TRANSFER IN OPTICALLY PUMPED ORGANIC SEMICONDUCTOR THIN-FILMS

Citation
Vg. Kozlov et al., STUDY OF LASING ACTION BASED ON FORSTER ENERGY-TRANSFER IN OPTICALLY PUMPED ORGANIC SEMICONDUCTOR THIN-FILMS, Journal of applied physics, 84(8), 1998, pp. 4096-4108
Citations number
52
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics, Applied
Journal title
ISSN journal
0021-8979
Volume
84
Issue
8
Year of publication
1998
Pages
4096 - 4108
Database
ISI
SICI code
0021-8979(1998)84:8<4096:SOLABO>2.0.ZU;2-O
Abstract
We present a study of optically pumped waveguide and microcavity laser s based on vacuum-deposited thin films of small molecular weight organ ic semiconductors. Lasing action in waveguide lasers is characterized by high output peak power (50 W), high differential quantum efficiency (70%) low lasing threshold (1 mJ/cm(2)), and long operational lifetim e (>10(6) laser pulses at 100 times the threshold pump power). Microca vity laser characteristics include 3 W peak output power, 300 mu J/cm( 2) lasing threshold, and lifetimes of >10(6) pump laser pulses (operat ing at 6 times the threshold power). We demonstrate wavelength variabi lity from 460 to 700 nm by changing the composition of the organic fil ms. The confinement of excitations on the dopant molecules leads to qu antum dot-like behavior such as high temperature stability of the lasi ng threshold, output power, and emission wavelength in the temperature range from 0 to 140 degrees C. The linewidth of laser emission from m icrocavity structures is found to be 0.2 +/- 0.1 Angstrom and is trans form limited by 40 ps long relaxation oscillations. We present a theor etical estimate for the linewidth of organic semiconductor laser emiss ion which is found to be at least an order of magnitude smaller than f or inorganic laser diodes. The prospects for realizing electrically pu mped organic semiconductor lasers are considered. (C) 1998 American In stitute of Physics. [S0021-8979(98)07520-3].