Photorefractive molecular composite bearing the phenothiazine derivatives

We report the characteristics of the diffraction behavior of the photorefractive (PR) molecular materials that contains the phenothiazine derivatives. Diphenylhydrazine and malononitrile were reacted with N-alkyl substituted phenothiazinyl aldehyde to provide the charge transporting and nonlinear optical(NLO) chromophore, respectively. The resultant phenothiazine derivatives were employed to fabricate the efficient photorefractive media either without or with 2,4,7-trinitrofluorenone (TNF). The prepared molecular samples can contain the very high NLO chromophore (50-100 wt%). We showed very unusual complementary grating to reduce the hole transport/trap effect from pure photorefractivity and how to control the counter-effect from the electron transport/trap phenomena. Adding the specific molecules to the host PR materials reduced the electron transport effect that is responsible for the complementary grating, thereby causing a dominant contribution of hole transport effect to the grating formation and erasing processes.