Photoinduced Birefringence of Azodye-Doped Materials by a Femtosecond Laser

Birefringence in azodye-doped polymethylmethacrylate and azodye-doped silica hybrid materials was induced by the twophoton excitation of a femtosecond laser. The growth and the relaxation characteristics of the photoinduced birefringence in the two types of material were investigated, and the probe transmittance for the induced birefringence was estimated to be 92%. Furthermore, an optical image storage based on this photoinduced birefringence was demonstrated.