Abstract

Nonlinear optical processes offer mechanisms necessary to substitute optically active materials or complement current technologies for switches, modulators, and memories.¹ Recent research in this area has centered around a search for materials with high nonlinear susceptibilities [X(2), etc.] and for methods to fabricate sturctures that would facilitate such applications.¹ Some organic materials are known to have unusually large susceptibilities.¹·² A merocyanine dye was found to have the largest known β (10⁻²⁷ esu). Ordered thin films of these materials can be made using the Langmuir/Blodgett (L/B) deposition technique in which monomolecular layers ~30 Å thick are sequentially transferred to a substrate from an air-water Interface.^3,4 Here we report the observation of SHG from multilayered structures each made entirely of one material. This includes multilayers of the hemicyanlne dye mixed with a polymer (PMMA) as well as multilayers of the dye itself.

© 1986 Optical Society of America