Polarized photoluminescence from solid films of nematic and chiral-nematic poly(p-phenylene)s
Thermotropic nematic and chiral-nematic poly(p-phenylene)s were prepared into well-aligned films between fused-silica substrates in which conjugated backbones were uniaxially and helically oriented. With unpolarized photoexcitation at 350 nm, a nematic film produced a degree of linear polarization of 9 near the emission peak at 410 nm with no evidence of excimer formation. With the same photoexcitation of a chiral-nematic film, the degree of circular polarization was found to vary from -1.3 in the 390--430 nm spectral region to between +0.3 and +0.9 beyond the edge of the selective reflection band. The crossover behavior unique to light emission from the selective reflection region remains inexplicable with existing theories on light propagation through periodically structured films.
- Sponsoring Organization:
- (US)
- OSTI ID:
- 40205307
- Journal Information:
- Applied Physics Letters, Vol. 77, Issue 19; Other Information: DOI: 10.1063/1.1323548; Othernumber: APPLAB000077000019002982000001; 012045APL; PBD: 6 Nov 2000; ISSN 0003-6951
- Publisher:
- The American Physical Society
- Country of Publication:
- United States
- Language:
- English
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