Photorefractive polymer composites are an unusually sensitive class of photopolymers. Physics of Photorefraction in Polymers describes our current understanding of the physical processes that produce a photorefractive effect in key composite materials. Topics as diverse as charge generation, dispersive charge transport, charge compensation and trap

The future of information technology requires ultra high speed processing and large data storage capacity. Since the electronics technology using semi conduc tors and inorganic materials is about to reach its limits, much current research is focused on utilizing much faster photons than electrons, namely photonics. To achieve any significant effect on the actual use of the science of photonics, devel opments of more efficient photonics materials, better optical property evaluations, manufacture of devices for system applications, etc. are the subjects which need to be explored. In particular, the development of photonics materials stands in the forefront of research as this constitutes the most pertinent factor with regard to the development of ultra high speed and large capacity information processing. In this respect, there has been continuous research on photo responsive materials through molecular structure design and architecture and the results so far are very promising as functions and performances are beginning to realize their high expectations. The two special volumes "Polymers for Photonics Applications" give authorita tive and critical reviews on up to date activities in various fields of photonic poly mers including their promising applications. Seven articles have been contributed by internationally recognized and they deal with, polymers for second and third order nonlinear optics, quadratic parametric interactions in polymer waveguides, electroluminescent polymers as light sources, photoreflective polymers for holo graphic information storage, and highly efficient two photon absorbing organics and polymers.

This second volume of the series on photorefractive effects focuses on the most recent developments in the field and highlights the parameters which govern the photoinduced nonlinearity. Besides reviewing conventional electro-optic crystals, this book deals with organic photorefractive materials, giving an in-depth assessment of the present understanding of the effect in a variety of materials. The materials considered in this volume will play a significant role in the development of applications such as presented in the third volume.

The goal of this project was to produce and characterize improved organic ferroelectric materials with emphasis on improving the response time and sensitivity. We demonstrated 300-fold improvements in the mobility of photorefractive polymer composites by identifying and mitigating the dipolar disorder mobility-reducing mechanism endemic to organic photorefractive materials and choosing transport agents that were relatively insensitive to this mechanism. We also synthesized dendrimers with design features further reducing dipolar disorder and also the significant van der Waals disorder for use in improved-speed photorefractive composites.

This is the first volume of a set of three within the Springer Series in Optical Sciences, and is devoted to photorefractive effects, photorefractive materials, and their applications. Since the publication of our first two Springer books on Photorefractive Materials and Their Applications (Topics in Applied Physics, Vols. 61 and 62) almost 20 years ago, a lot of research has been done in this area. New and often expected effects have been discovered, theoretical models developed, known effects finally explained, and novel applications proposed. We believe that the field has now reached a high level of maturity, even if research continues in all areas mentioned above and with new discoveries arriving quite regularly. We therefore have decided to invite some of the top experts in the field to put together the state of the art in their respective fields. This after we had been encouraged to do so for more than ten years by the publisher, due to the fact that the former volumes were long out of print.

Photorefractive materials combine photoconductive and electro-optic properties: light affects their electrical conductivity; their optical properties (refractive index, etc.) are affected by applied electric fields. The aim of this book is to cover the vast range of phenomena occurring in Photorefractive Materials. For Physicists it is part of the fashionable subject of Nonlinear Optics. Engineers tend to place it as part of optoelectronics promising a variety of new devices. This book summarizes the results of 28 years of research in a manner that would appeal both to the beginner (a graduate student who has just entered the field) and to the expert (who might have done research on some aspect of the subject for a decade or more). It is in three parts. Part I serves as an introduction with emphasis on physical principles and simple mathematical models. Part II is a comprehensive account of all the major advances. Its main merit is the organization of the material accompanied by a detailed list of references. Part III is concerned with the enormous range of potential applications.