Exciton annihilation studies in poly(p-phenylene vinylene)
- Sandia National Labs., Albuquerque, NM (United States)
- Donnelly Corp., Tucson, AZ (United States)
To verify the excitonic nature of the light-emitting state in PPV, fluorescence intensities and decay lifetimes were investigated as a function of excitation intensity. The results agree with the behavior predicted by the molecular exciton model. In particular, exciton-exciton annihilation causes the fluorescence intensity to saturate and the fluorescence lifetime to shorten at high exciton densities. In addition, the exciton annihilation, and thus diffusion, coefficients are found to be relatively large, even at low temperatures, indicating that exciton migration is important in PPV. These results indicate that the fluorescent (photoluminescent) state in PPV is excitonic in nature. The results argue against the band model where high mobility at reduced temperatures is not expected because the light-emitting species, neutral bipolarons, are associated with large lattice distortions.
- Research Organization:
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC04-94AL85000
- OSTI ID:
- 102127
- Report Number(s):
- SAND-95-1767C; CONF-951033-18; ON: DE95016463; TRN: AHC29524%%7
- Resource Relation:
- Conference: 27. international technical conference of the Society for the Advancement of Material and Process Engineering (SAMPE): diversity into the next century, Albuquerque, NM (United States), 9-12 Oct 1995; Other Information: PBD: [1995]
- Country of Publication:
- United States
- Language:
- English
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