Complementary grating dynamics in photorefractive polymers with Alq

摘要

The electron transporting molecule tris(8-hydroxyquinoline) aluminum (A1q_3) was introduced into a photorefractive composite in a low density to study the effects of electron traps on the performance. Compared to a control sample, Alq_3 samples exhibited higher dielectric strength, over-modulation at reduced voltage, and increased writing speed. Transient measurements indicated grating revelation via decay of a competing grating. The dynamics are consistent with a bipolar charge transport model. Overall, Alq_3 improves the sensitivity, trapping, and breakdown voltage without significant losses in absorption or phase stability.