Photorefractive dynamics in poly(triarylamine)-based polymer composites

The photorefractive (PR) response and dynamics are investigated in a methyl-substituted poly(triarylamine) (PTAA)-based PR composite. The charge transfer complex between PTAA and an added small amount of second acceptor, (tris(8-hydroxyquinolinato)aluminium) Alq(3), effectively suppresses the photoconductivity, and thus the sample is able to withstand the dielectric breakdown at a high electric field. The resulting PR response is enhanced at a higher electric field. Sub-millisecond PR response times were observed for both optical diffraction and optical amplification: i.e., 350 μs for optical amplification and 860 μs for optical diffraction observed under 532 nm illumination (0.534 W cm(-2)) at 60 V μm(-1). The response time of optical amplification followed the photocurrent response time of 367 μs.