1. Nonlinear transmission and excited-state absorption in fluorene derivatives
- Author
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Belfield, Kevin D., Bondar, Mykhailo V., Hernandez, Florencio E., Morales, Alma R., Przhonska, Olga V., and Schafer, Katherine J.
- Subjects
Optics -- Research ,Astronomy ,Physics - Abstract
The nonlinear transmission and the excited-state absorption spectra of three fluorene derivatives exhibiting large two-photon absorptivity were measured by the third harmonic of a picosecond Nd:YAG laser. We analyzed their capability for exhibiting stimulated emission in polar solvents and found that asymmetrical fluorene compounds with a diphenylamino substituent exhibited large Stokes shifts (~8000 [cm.sup.-1]), high quantum yields (~0.9 - 1.0), and no optical gain over their entire fluorescence spectral region. In contrast, a symmetrical fluorene derivative with vinylphenylbenzothiazole substituents in positions 2 and 7 underwent lasing under one-photon excitation by use of picosecond pulsed irradiation. OCIS codes: 140.3380, 140.4480, 160.3380, 160.4890, 190.4710.
- Published
- 2004