NONLINEAR OPTICAL MEDIUM OF COPOLYMER

摘要

PURPOSE: To obtain the copolymer medium which shows a high-level nonlinear optical response by forming a copolymer film having a crystallographic molecular orientation in the flat film surface and a dipolar molecular orientation perpendicular to the film surface. CONSTITUTION: This copolymer medium has a crystallographic molecular orientation in the flat film surface and a dipolar molecular orientation perpendicular to the film surface and shows an about >=1×10<-8> esu secondary nonlinear optical susceptibility measured at a 1.91μm excitation wavelength. The dipolar molecular orientation is induced by poling a copolymer material of the medium through application of an electric field and the crystallographic molecular orientation in the flat film surface is attained by application of uniaxial or biaxial stress or a magnetic field to the copolymer material. The resulting copolymer having such two mode molecular orientations shows both nonlinear optical properties and piezoelectric properties. Thus, the objective copolymer nonlinear optical medium which has stable two mode molecular orientations and the initial high- level secondary linear optical susceptibility of which can be maintained, is obtained.