It is a pleasure to write a few words as an introduction to the proceedings of the 1980 NATO ASI on "Physical Processes in Laser Naterial Interaction." This ASI is the ninth course of a series devoted to lasers and their applications, held under the responsibility of the Quantum Electronics Division of the European Physical Society, and for this reason known as the "Europhysics School of Quantum Electronics." Since 1971 the School has been operating with the joint direc tion of myself as representative of the academic research, and Dr. D. Roess (formerly with Siemens AEG, Munich, and now with Sick, Optik und Electronik, GmbH, Munich) for the industrial applications. Indeed the aim of the School is to alternate fundamental and applied frontier topics in the area of quantum electronics and modern optics, in order to introduce young research people from universities and industrial R&D laboratories to the new aspects of research opened by the laser."

The Workshop on Physics and Application of Non-crystalline Semiconductors in Optoelectronics was held from 15 to 17 October 1996 in Chisinau. republic of Moldova and was devoted to the problems of non-crystalline semiconducting materials. The reports covered two mjlin topics: theoretical basis of physics of non -crystalline materials and experimental results. In the framework of these major topics there were treated many subjects. concerning the physics of non-crystalline semiconductors and their specific application: -optical properties of non-crystalline semiconductors; -doping of glassy semiconductors and photoinduced effects in chalcogenide glasses and their application for practical purposes; -methods for investigation of the structure in non-crystalline semiconductors -new glassy materials for IR trasmittance and optoelectronics. Reports and communications were presented on various aspects of the theory. new physical principles. studies of the atomic structure. search and development of optoelectronics devices. Special attention was paid to the actual subject of photoinduced transformations and its applications. Experimental investigations covered a rather wide spectrum of materials and physical phenomena. As a novel item it is worth to mention the study of nonlinear optical effects in amorphous semiconducting films. The third order optical non linearities. fast photoinduced optical absorption and refraction. acusto-optic effects recently discovered in non-crystalline semiconductors could potentially be utilised for optical signal processing. The important problems of photoinduced structural transformations and related phenomena. which are very attractive and actual both from the scientific and practical points of view. received much attention in discussions at the conference."

This book is based on the contributions to the 17th International School of Materials Sci ence and Technology, entitled Nonlinear Waves in Solid State Physics. This was held as a NATO Advanced Study Institute at the Ettore Majorana Centre in Erice, Sicily between the st th 1 and 15 July 1989, and attracted almost 100 participants from over 20 different countries. The book covers the fundamental properties of nonlinear waves in solid state materials, dealing with both theory and experiment. The aim is to emphasise the methods underpinning the important new developments in this area. The material is organised into subject areas that can broadly be classified into the following groups: the theory of nonlinear surface and guided waves in self-focusing magnetic and non-magnetic materials; nonlinear effects at in terfaces; nonlinear acoustoelectronic and surface acoustic waves; Lagrangian and Hamiltonian formulations of nonlinear problems; nonlinear effects in optical fibres; resonance phenomena; and nonlinear integrated optics. The chapters have been grouped together according to these classifications as closely as possible, but it should be borne in mind that although there is much overlap of ideas, each chapter is essentially independent of the others. We would like to acknowledge the sponsorship of the NATO Scientific Affairs Division, the European Physical Society, the National Science Foundation of the USA, the European Research Office, the Italian Ministry of Education, the Italian Ministry of Scientific and Technological Research, the Sicilian Regional Government and the Ugo Bordoni Foundation.

The Workshop on Physics and Application of Non-crystalline Semiconductors in Optoelectronics was held from 15 to 17 October 1996 in Chisinau. republic of Moldova and was devoted to the problems of non-crystalline semiconducting materials. The reports covered two mjlin topics: theoretical basis of physics of non -crystalline materials and experimental results. In the framework of these major topics there were treated many subjects. concerning the physics of non-crystalline semiconductors and their specific application: -optical properties of non-crystalline semiconductors; -doping of glassy semiconductors and photoinduced effects in chalcogenide glasses and their application for practical purposes; -methods for investigation of the structure in non-crystalline semiconductors -new glassy materials for IR trasmittance and optoelectronics. Reports and communications were presented on various aspects of the theory. new physical principles. studies of the atomic structure. search and development of optoelectronics devices. Special attention was paid to the actual subject of photoinduced transformations and its applications. Experimental investigations covered a rather wide spectrum of materials and physical phenomena. As a novel item it is worth to mention the study of nonlinear optical effects in amorphous semiconducting films. The third order optical non linearities. fast photoinduced optical absorption and refraction. acusto-optic effects recently discovered in non-crystalline semiconductors could potentially be utilised for optical signal processing. The important problems of photoinduced structural transformations and related phenomena. which are very attractive and actual both from the scientific and practical points of view. received much attention in discussions at the conference."

Introduction to Integrated Optics: Characterization and Modeling of Optical Waveguides (S. Pelli, G. Righini). Introduction to Nonlinear Guided Waves (M. Bertolotti). Nonlinear Optical Materials (C. Flytzanis). Integrated Optics in Lithium Niobate (D. Delacourt). Propagation of Selftrapped Optical Beams in Nonlinear Kerr Media and Photorefractive Crystals (B. Crosignani). Advances in Semiconductor Integrated Optics (A. Carenco). Silica on Silicon Integrated Optics (R.R. Syms). Integrated Optics on Silicon: IOS Technologies (S. Valette). Are Glasses Suitable for Optoelectronics? (A. Montenero). Linear and Nonlinear Optical Properties of Polymer Waveguides (F. Michelotti). Fabrication and Characterization of Conjugated Polymer Waveguides (S. Sottini). Linearized Optical Modulators for High Performance Analog Links (G. Tangonan et al.). Alloptical Switching in AlGaAs Semiconductor Wavelength Devices (J.A. Aitchison). Integrated Optics Sensors (O. Parriaux). Spatial Optical Solitonsexperiments (Y. Silberberg). Optical Losses of Characterization of Channel Waveguide through Photodeflection Method (R. Li Voti et al.). 7 additional articles. Index.