Poling and characterization of nonlinear polymer DCNP/PEK-c thin films

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 poling profiles of the polymer film were investigated by using the in situ second-harmonic generation (SHG) measurement. The corona poling condition was optimized by the poling profiles. The second-order nonlinear optical (NLO) coefficient χ33(2)=20.86 pm/V at λ=1064 nm was determined by using the Maker fringe method after poling under the optimal poling condition. The temperature stability of the second-order optical properties of the poled polymer film was measured by the in situ SHG intensity probing. Moreover, the relaxation of the electric field-induced polar orientation of the chromophores in the poled polymer film was measured by the thermally stimulated discharge current (TSDC) technique.