Photorefractive effect of a novel conjugate polymer containing transition metal complex

The photorefractive effect (PR) of a novels σ-π alternating polymer having 2,2'-bipyridyl in the polymer backbone and their ruthenium complexes has been investigated. The ruthenium complex was used as the charge generator, the σ-π alternating polymer backbone as the charge transporting channel and second-order nonlinear (NLO) optical chromophore. The photorefractive properties were demonstrated by two-beam coupling (2BC), degenerated four-wave mixing (DFWM) and field-induced orientation birefringence at wavelength of 532 nm. This polymer shows a enhanced photorefractive effect due to the efficient photoinduced metal-to-ligand charge transfer (MLCT) inside the ruthenium complex. A net optical gain of about 22 cm^-1 and the diffraction efficiency about 10% were obtained at the external electric field of 30 V/μm. Received 21 December 1999 and Received in final form 7 July 2001