Oriented Molecular Systems

Photonics and optoelectronics are becoming important for information storage and data transport due to their speed and bandwidth. Nonlinear optics is a key element for photonic applications since light can be controlled by light. Both second-order and third-order nonlinear optical effects are potentially important for photonic applications and are subjects of intense current materials and optical research. There are many different scientific and technological issues involved in developing materials for nonlinear optics. In this work we concentrate on second-order nonlinearities. Furthermore, we narrow the scope of this review to organic thin films fabricated by molecular assembly techniques, mainly Langmuir-Blodgett (LB) Films [ 1 ]. Self-assembly techniques will be mentioned briefly. Monolayers on the water surface will not be treated here. Electro-optic polymers and crystalline thin films will only be referred to for comparison.