Large photoinduced refractive index changes of a polymer containing photochromic norbornadiene groups

Abstract

We prepared a polymer containing pendant norbornadiene (NBD) moieties, P(MMA 0.43 -co-GMA 0.57 -PNCA) , and measured absorbance and refractive indexspectra before and after photoisomerization of norbornadiene moieties. Large photoinduced refractive index changes of ∼0.01 were obtained at 632.8 nm, the region far from the absorption band. A quantum yield of 0.50 was obtained for the photoisomerization of NBD moieties in this polymer. These values are sufficient to make efficient channel waveguides by photoisomerization.