Ultrafast photoinduced anisotropy and optical switching in azobenzene sidechain polymers

Abstract

Photoinduced anisotropic and optical switching properties have been studied in two kinds of azobenzene sidechain polymers, a disazobenzene sidechain polymer (DAP–PGMA) and a monoazobenzene sidechain polymer P(MMA–co–MAZ). Picosecond optical switching dynamics have been observed in both DAP–PGMA and P(MMA–co–MAZ) films. The rise time of the optical switching in DAP–PGMA film is about 40 ps, which is much faster than that of P(MMA–co–MAZ) film (∼100 ps). DAP–PGMA shows enhanced photoanisotropy and larger birefringence (∼7.04×10−4) than that of P(MMA–co–MAZ) (∼1.34×10−4). The influence of the azobenzene sidechain groups on the photoanisotropic dynamics is discussed.