2018 Volume 31 Issue 6 Pages 711-717
Pseudo photorefractive effect was observed in composites based on polyacrylate containing 9-oxo-9H-thioxanthene-10,10-dioxide (TH) moiety doped with 4-(N,N-diethylamino)-β-nitrostyrene (DEANST), and in copolymers with both moieties without an external electric field. Lowering glass transition temperature of the composites by the addition of a low molecular weight plasticizer decreased the gain coefficients, and unstable index grating. Due to the fact that the addition of stronger electron donating carbazole derivative also made the gain coefficient lower, charge transfer interaction between TH and DEANST plays an important role to establish the grating. Compared with the composite systems, the corresponding copolymers required the longer time to reach the saturated gain coefficient, indicating that the mass transfer of the electro-optically active moiety was essential to create the phase-shifted index grating with the interference pattern.
