Nonlinear Optical Materials

Abstract

The telecommunications field is developing further and further, and needing ultrahigh speed information processing and transmission of large amounts of information. There is not enough bandwidth in current electronic networks, for example in the application fields such as data browsing on the world wide web (WWW) and video conferencing. Optical communication technologies (processing of large amounts of information with optical devices) are expected in information transmission and processing systems, by advancement in high-speed digital switching, fiber optics and improved networking software. The use of fiber optics permits transmission of data without repeaters and affords enormous bandwidth potential. The bulk of the devices in these systems for long-distance transmission use and/or for high-accuracy processing use will be fabricated from inorganic semiconductors, but organic materials have high potentialities for short-distance waveguide and high-speed switching. Low-loss, inexpensive optical waveguides and very high bandwidth, integrated optical modulators are two of the major areas where polymer and organic materials can be expected to be used. For both of these applications, the key materials issue is whether the polymer electro-optic (EO) materials can be developed with sufficiently large EO effects, low optical loss, and good long-term stability. Organic nonlinear optical (NLO) materials have attracted much attention due to their high potentiality for high NLO effects, i.e.the second and third nonlinear effects. Optical storage/memory is also an important field in real-time holography applications, in which photorefractive materials are key.