M. G. Harrison, K. E. Ziemelis, R. H. Friend, P. L. Burn and A. B. Holmes.
Synthetic Metals 55:1 (1993) p218-223 .
We have investigated metal-insulator-semiconductor structures fabricated with poly(2,5-dimethoxy-p-phenylene vinylene) as the active semiconductor. In accumulation, we have observed three charge- related absorption features at 0.7eV, 1.7eV and 2.0eV which scale in intensity with the field-induced charge present in the device accumulation layer. We note that the two lower transitions are due to the same state, which can be associated with the presence of long- lived bipolarons, observed in photo-induced absorption. We estimate a value for the optical cross-section associated with the bipolaron absorption at 0.7eV, of around 2 x 10(-15)cm2.
I. D. Parker, R. W. Gymer, M. G. Harrison, R. H. Friend and H. Ahmed.
Applied Physics Letters 62:13 (1993) p1519-1521 .
We report an electro-optic absorption modulator based around a metal- insulator-semiconductor field-effect transistor structure in which the active semiconductor is the polymer poly(2,5-dimethoxy-p- phenylene vinylene). It incorporates a single optical waveguide formed by the polymer, insulator, and a polyimide top layer which is ribbed to define the guide laterally. Charge injection creates polaron and bipolaron states which change the subgap absorption between 2 and 1.4 mum and between 800 nm and the band edge at 600 nm.
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Mark Harrison firstname.lastname@example.org, Marburg, May 3, 1998