High Two-Beam Coupling Coefficients of Monolithic Small Molecule at Low Electric Field

A novel full-functional photorefractive small molecular material, (9-ethyl-9H-carbazol-3-ylmethylene)-(4-nitro-phenyl)-amine (ECYENPA), was synthesized and its photorefractivity was studied by two-beam coupling experiments at a wavelength of 632.8 nm. The glass transition temperature of ECYENPA, as low as −5 degrees C, results in the chromophore being orientated easily at room temperature. High two-beam coupling coefficient was obtained to be 232 cm−1 at an electric field of 44.6 V/μm.