| 摘要 |
PURPOSE:To obtain the optical waveguide having a high nonlinear optical constant by confining light between an ion implanted layer of a low refractive index implanted with ions down to a prescribed depth from a substrate surface and the substrate sur face. CONSTITUTION:Domain inversion parts 3 are formed on the surface of the nonlinear optical crystalline substrate consisting of an LiNbO3 crystal 1, etc., in such a manner that the domain inversion period (distance d) of the polarization attains the same length as twice the coherent length or the length of the odd times of twice the coherent length by deffusing Ti with lift-off lithography, etc. The ions of He<+>, etc., are then implanted in the part of the optical waveuide 2 in such a manner that the ions are implanted to the prescribed depth (1 to several mum) from the substrate surface. This part has the refractive index lower than the refractive index of other substrate materials and the confining of the light between the ion implanted layer and the substrate surface is possible. The optical waveguide 2 is thus formed. The optical waveguide part 2 is not subjected to chemical denaturation and has the nonlinear optical constant of the substrate itself and, therefore, high wavelength conversion efficiency is obtd. |
