Investigation on the nonlinear optical properties of the DCNP/PEK-c guest-host polymer films

The polyetherketone (PEK-c) guest-host polymer thin films doped with 3-(1,1 -dicyanothenyl)-1-phenyl-4,5-dihydro-1H-pryazole (DCNP) were prepared. The polymer films were investigated with in situ second-harmonic generation (SH G) measurement. The corona poling temperature was optimized by the temperat ure dependence of the in situ SHG signal intensity under the poling electri c field applying. The temporal and temperature stability of the second-orde r properties of the poled polymer film were measured by the in situ SHG sig nal intensity probing. The second-order NLO coefficient chi ((2))(33) = 32. 65 pm/V at lambda = 1064 nm was determined by using the Makel fringe method after poling under the optimal poling condition. The dispersion of the NLO coefficient of the guest-host polymer system was determined by the measure d value of chi ((2))(33) at 1064 nm and the two-level model.