We investigated efficient surface-emitting second-harmonic-generation devices in poled polymers, using a 4-dimethylamino-4′-nitrostilbene side-chain polymer. The investigation included characterization of the linear and nonlinear optical properties of the polymer, design of efficient surface-emitting second-harmonic-generation devices based on poled polymers, development of an efficient in-plane poling technique, and demonstration of surface-emitting second-harmonic generation in poled polymers. As a result, strong field in-plane parallel poling was successfully performed with poling fields over 300 V/μm, which led to a large nonlinearity of 150 pm/V at 1064 nm (near resonance). A thick cover layer and a highly resistive substrate were found to be essential for efficient in-plane poling without breakdown at relatively small fields and significant charge injection. We achieved quasi-phase matching in the transverse direction by fabricating nonlinear–linear multilayer waveguides. Each layer had approximately a 150-nm thickness. The largest second-harmonic power conversion efficiency to date in the poled-polymer devices is 0.6%/W cm, which is comparable with those of semiconductor multilayer devices.
© 1998 Optical Society of America
Akira Otomo, George I. Stegeman, Marinus C. Flipse, Mart B. J. Diemeer, Winfried H. G. Horsthuis, and Guus R. Möhlmann, "Nonlinear contrawave mixing devices in poled-polymer waveguides," J. Opt. Soc. Am. B 15, 759-772 (1998)