Claude Weisbuch – författare

In its original form, this widely acclaimed primer on the fundamentals of quantized semiconductor structures was published as an introductory chapter in Raymond Dingle''s edited volume (24) of Semiconductors and Semimetals. Having already been praised by reviewers for its excellent coverage, this material is now available in an updated and expanded "student edition." This work promises to become a standard reference in the field. It covers the basics of electronic states as well as the fundamentals of optical interactions and quantum transport in two-dimensional quantized systems. This revised student edition also includes entirely new sections discussing applications and one-dimensional and zero-dimensional systems.- Available for the first time in a new, expanded version- Provides a concise introduction to the fundamentals and fascinating applications of quantized semiconductor structures

In its original form, this widely acclaimed primer on the fundamentals of quantized semiconductor structures was published as an introductory chapter in Raymond Dingle's edited volume (24) of Semiconductors and Semimetals. Having already been praised by reviewers for its excellent coverage, this material is now available in an updated and expanded "student edition." This work promises to become a standard reference in the field. It covers the basics of electronic states as well as the fundamentals of optical interactions and quantum transport in two-dimensional quantized systems. This revised student edition also includes entirely new sections discussing applications and one-dimensional and zero-dimensional systems.

The optical properties of semiconductors have played an important role since the identification of semiconductors as "small" bandgap materials in the thinies, due both to their fundamental interest as a class of solids baving specific optical propenies and to their many important applications. On the former aspect we can cite the fundamental edge absorption and its assignment to direct or indirect transitions, many-body effects as revealed by exciton formation and photoconductivity. On the latter aspect, large-scale applications sucb as LEDs and lasers, photovoltaic converters, photodetectors, electro-optics and non-linear optic devices, come to mind. The eighties saw a revitalization of the whole field due to the advent of heterostructures of lower-dimensionality, mainly two-dimensional quantum wells, which through their enhanced photon-matter interaction yielded new devices with unsurpassed performance. Although many of the basic phenomena were evidenced through the seventies, it was this impact on applications which in turn led to such a massive investment in fabrication tools, thanks to which many new structures and materials were studied, yielding funher advances in fundamental physics.

The control of optical modes in microcavities or in photonic bandgap (PBG) materials is coming of age! Although these ideas could have been developed some time ago, it is only recently that they have emerged, due to advances in both atomic physics and in fabrication techniques, be it on the high-quality dielectric mirrors required for high-finesse Fabry­ Perot resonators or in semiconductor multilayer deposition methods. Initially the principles of quantum electro-dynamics (QED) were demonstrated in elegant atomic physics experiments. Now solid-state implementations are being investigated, with several subtle differences from the atomic case such as those due to their continuum of electronic states or the near Boson nature of their elementary excitations, the exciton. Research into quantum optics brings us ever newer concepts with potential to improve system performance such as photon squeezing, quantum cryptography, reversible taps, photonic de Broglie waves and quantum computers. The possibility of implementing these ideas with solid-state systems gives us hope that some could indeed find their way to the market, demonstrating the continuing importance of basic research for applications, be it in a somewhat more focused way than in earlier times for funding.

The optical properties of semiconductors have played an important role since the identification of semiconductors as "small" bandgap materials in the thinies, due both to their fundamental interest as a class of solids baving specific optical propenies and to their many important applications. On the former aspect we can cite the fundamental edge absorption and its assignment to direct or indirect transitions, many-body effects as revealed by exciton formation and photoconductivity. On the latter aspect, large-scale applications sucb as LEDs and lasers, photovoltaic converters, photodetectors, electro-optics and non-linear optic devices, come to mind. The eighties saw a revitalization of the whole field due to the advent of heterostructures of lower-dimensionality, mainly two-dimensional quantum wells, which through their enhanced photon-matter interaction yielded new devices with unsurpassed performance. Although many of the basic phenomena were evidenced through the seventies, it was this impact on applications which in turn led to such a massive investment in fabrication tools, thanks to which many new structures and materials were studied, yielding funher advances in fundamental physics.

The optical properties of semiconductors have played an important role since the identification of semiconductors as "small" bandgap materials in the thinies, due both to their fundamental interest as a class of solids baving specific optical propenies and to their many important applications. On the former aspect we can cite the fundamental edge absorption and its assignment to direct or indirect transitions, many-body effects as revealed by exciton formation and photoconductivity. On the latter aspect, large-scale applications sucb as LEDs and lasers, photovoltaic converters, photodetectors, electro-optics and non-linear optic devices, come to mind. The eighties saw a revitalization of the whole field due to the advent of heterostructures of lower-dimensionality, mainly two-dimensional quantum wells, which through their enhanced photon-matter interaction yielded new devices with unsurpassed performance. Although many of the basic phenomena were evidenced through the seventies, it was this impact on applications which in turn led to such a massive investment in fabrication tools, thanks to which many new structures and materials were studied, yielding funher advances in fundamental physics.

Low-dimensional materials are of fundamental interest in physics and chemistry and have also found a wide variety of technological applica­ tions in fields ranging from microelectronics to optics. Since 1986, several seminars and summer schools devoted to low-dimensional systems have been supported by NATO. The present one, Physics, Fabrication and Applications of Multilayered structures, brought together specialists from different fields in order to review fabrication techniques, charac­ terization methods, physics and applications. Artificially layered materials are attractive because alternately layering two (or more) elements, by evaporation or sputtering, is a way to obtain new materials with (hopefully) new physical properties that pure materials or alloys do not allow. These new possibilities can be ob­ tained in electronic transport, optics, magnetism or the reflectivity of x-rays and slow neutrons. By changing the components and the thickness of the layers one can track continuously how the new properties appear and follow the importance of the multilayer structure of the materials. In addition, with their large number of interfaces the study of inter­ face properties becomes easier in multilayered structures than in mono­ layers or bilayers. As a rule, the role of the interface quality, and also the coupling between layers, increases as the thickness of the layer decreases. Several applications at the development stage require layer thicknesses of just a few atomic layers.

Low-dimensional materials are of fundamental interest in physics and chemistry and have also found a wide variety of technological applica­ tions in fields ranging from microelectronics to optics. Since 1986, several seminars and summer schools devoted to low-dimensional systems have been supported by NATO. The present one, Physics, Fabrication and Applications of Multilayered structures, brought together specialists from different fields in order to review fabrication techniques, charac­ terization methods, physics and applications. Artificially layered materials are attractive because alternately layering two (or more) elements, by evaporation or sputtering, is a way to obtain new materials with (hopefully) new physical properties that pure materials or alloys do not allow. These new possibilities can be ob­ tained in electronic transport, optics, magnetism or the reflectivity of x-rays and slow neutrons. By changing the components and the thickness of the layers one can track continuously how the new properties appear and follow the importance of the multilayer structure of the materials. In addition, with their large number of interfaces the study of inter­ face properties becomes easier in multilayered structures than in mono­ layers or bilayers. As a rule, the role of the interface quality, and also the coupling between layers, increases as the thickness of the layer decreases. Several applications at the development stage require layer thicknesses of just a few atomic layers.

les Houches This Winter School on "The Physics and Fabrication of Microstructures" originated with a European industrial decision to investigate in some detail the potential of custom-designed microstructures for new devices. Beginning in 1985, GEC and THOMSON started a collaboration on these subjects, supported by an ESPRIT grant from the Commission of the European Com­ munity. To the outside observer of the whole field, it appears clear that the world effort is very largely based in the United States and Japan. It also appears that cooperation and dissemination of results are very well organised outside Europe and act as a major influence on the development of new concepts and devices. In Japan, a main research programme of the Research and Development for Basic Technology for Future Industries is focused on "Future Electron Devices". In Japan and in the United States, many workshops are organised annually in order to bring together the major specialists in industry and academia, allowing fast dissemination of advances and contacts for setting up cooperative efforts.

les Houches This Winter School on "The Physics and Fabrication of Microstructures" originated with a European industrial decision to investigate in some detail the potential of custom-designed microstructures for new devices. Beginning in 1985, GEC and THOMSON started a collaboration on these subjects, supported by an ESPRIT grant from the Commission of the European Com­ munity. To the outside observer of the whole field, it appears clear that the world effort is very largely based in the United States and Japan. It also appears that cooperation and dissemination of results are very well organised outside Europe and act as a major influence on the development of new concepts and devices. In Japan, a main research programme of the Research and Development for Basic Technology for Future Industries is focused on "Future Electron Devices". In Japan and in the United States, many workshops are organised annually in order to bring together the major specialists in industry and academia, allowing fast dissemination of advances and contacts for setting up cooperative efforts.

This set of lecture notes provides a detailed and up-to-date description of a field undergoing explosive growth, that of confined photon systems in the shape of microcavities or photonic crystals. Bringing together world leaders in the field, it provides all the basic tools needed to master a subject which will have both major impact in fundamental studies and widescale applications. Confined photon systems enable the study of low-dimensional photonic systems, modified light-matter interaction, e.g. between excitons and photons in all-solid-state semiconductor microcavities, and of many phenomena of quantum optics, including single photon generation, squeezed light, quantum state entanglement, non-local quantum measurements, and, potentially, quantum computation. They are also on the verge of yielding new, high performance optical devices for large-scale industries such as telecommunications and display technology.

The control of optical modes in microcavities or in photonic bandgap (PBG) materials is coming of age! Although these ideas could have been developed some time ago, it is only recently that they have emerged, due to advances in both atomic physics and in fabrication techniques, be it on the high-quality dielectric mirrors required for high-finesse Fabry­ Perot resonators or in semiconductor multilayer deposition methods. Initially the principles of quantum electro-dynamics (QED) were demonstrated in elegant atomic physics experiments. Now solid-state implementations are being investigated, with several subtle differences from the atomic case such as those due to their continuum of electronic states or the near Boson nature of their elementary excitations, the exciton. Research into quantum optics brings us ever newer concepts with potential to improve system performance such as photon squeezing, quantum cryptography, reversible taps, photonic de Broglie waves and quantum computers. The possibility of implementing these ideas with solid-state systems gives us hope that some could indeed find their way to the market, demonstrating the continuing importance of basic research for applications, be it in a somewhat more focused way than in earlier times for funding.