2ND HARMONIC-GENERATION IN CORONA POLED, DOPED POLYMER-FILMS AS A FUNCTION OF CORONA PROCESSING

A novel technique for examining corona processing variables in thin-film organic second-order nonlinear optical materials is discussed. Positive and negative polarity dc-coronas were used to pole doped glassy polymer films in situ at room temperature in air, helium, and nitrogen environments to create materials capable of second harmonic generation (SHG). Films are poled in the beam path and are continuously sampled. For a given atmosphere and poling time, films poled in a positive corona show greater SHG intensities than those poled with negative coronas. The temporal stability of the SHG intensity for films poled with a positive corona increases from air to nitrogen to helium, and for a negative corona is similar in nitrogen and helium atmospheres, and less stable in air. Possible mechanisms are discussed.