We began planning and writing this book in the late 1970s at the suggestion of Manuel Cardona and Helmut Lotsch. We also received considerable en couragement and stimulation from colleagues. Some said there was a need for instructional material in this area while others emphasized the utility of a research text. We tried to strike a compromise. The figures, tables, and references are included to enable researchers to obtain quickly essential information in this area of semiconductor research. For instructors and stu dents, we attempt to cover some basic ideas about electronic structure and semiconductor physics with applications to real, rather than model, solids. We wish to thank our colleagues and collaborators whose research re sults and ideas are presented here. Special thanks are due to Jim Phillips who influenced us both during our formative years and afterwards. We are grateful to Sari Yamagishi for her patience and skill with the typing and production of the manuscript. Finally, we acknowledge the great patience of Helmut Lotsch and Manuel Cardona. Berkeley, CA M.L. Cohen Minneapolis, MN, J.R. Chelikowsky March 1988 VII Contents 1. Introduction............................................... 1 2. Theoretical Concepts and Methods ..................... 4 2.1 The One-Electron Model and Band Structure............ 7 2.2 Properties of En(k) ...................................... 11 3. Pseudopotentials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 . . . . . . . . . . . . 3.1 The Empirical Pseudopotential Method.................. 20 3.2 Self-Consistent and Ab Initio Pseudopotentials ........... 25 4. Response Functions and Density of States .............. 30 4.1 Charge Density and Bonding ................... . . . . . . . . . 38 .

It is widely recognized that an understanding of the optical pro perties of matter will give a great deal of important information re levant to the fundamental physical properties. This is especially true in semiconductor physics for which, due to the intrinsic low screening of these materials, the optical response is quite rich. Their spectra reflect indeed as well electronic as spin or phonon transitions. This is also in the semiconductor field that artificial structures have been recently developed, showing for the first time specific physical properties related to the low dimentionality of the electronic and vi bronic properties : with this respect the quantum and fractional quan tum Hall effects are among the most well known aspects. The associated reduced screening is also a clear manifestation of these aspects and as such favors new optical properties or at least significantly enhan ces some of them. For all these reasons, it appeared necessary to try to review in a global way what the optical investigation has brought today about the understanding of the physics of semiconductors. This volume collects the papers presented at the NATO Advanced study Inst i tut e on "Optical Properties of Semiconductors" held at the Ettore Majorana Centre, Erice, Sicily on March 9th to 20th, 1992. This school brought together 70 scientists active in research related to optical properties of semiconductors. There were 12 lecturers who pro vided the main contributions .

This book is an account of the manner in which the optical phenomena observed from solids relate to their fundamental properties. Written at the graduate level, it attempts a threefold purpose: an indication of the breadth of the subject, an in-depth examination of important areas, and a text for a two-semester course. The first two chapters present introductory theory as a foundation for subsequent reading. The following ten chapters broadly concern electronic properties associated with semiconductors ranging from narrow to wide energy gap materials. Lattice properties are examined in the remaining chap ters, in which effects governed by phonons in perfect crystals, point defects, their vibrational and electronic spectra, and electron-phonon interactions are stressed. Fun and hard work, both in considerable measure, have gone into the preparation of this volume. At the University of Freiburg, W. Germany, from August 7-20, 1966, the occasion of a NATO Advanced Study Institute on "The Optical Properties of Solids," the authors of these various chapters lectured for the Institute; this volume provides essentially the "Proceed ings" of that meeting. Many major revisions of original lectures (contrac tions and enlargements) were required for better organization and presentation of the subject matter. Several abbreviated chapters appear mainly to indicate the importance of their contents in optical properties research and to indicate recently published books that provide ample coverage. We are indebted to many people: the authors for their efforts and patience; our host at the University of Freiburg, the late Professor Dr.

Captures the most up-to-date research in the field, written in an accessible style by the world's leading experts.

A graduate textbook presenting the underlying physics behind devices that drive today's technologies. The book covers important details of structural properties, bandstructure, transport, optical and magnetic properties of semiconductor structures. Effects of low-dimensional physics and strain - two important driving forces in modern device technology - are also discussed. In addition to conventional semiconductor physics the book discusses self-assembled structures, mesoscopic structures and the developing field of spintronics. The book utilizes carefully chosen solved examples to convey important concepts and has over 250 figures and 200 homework exercises. Real-world applications are highlighted throughout the book, stressing the links between physical principles and actual devices. Electronic and Optoelectronic Properties of Semiconductor Structures provides engineering and physics students and practitioners with complete and coherent coverage of key modern semiconductor concepts. A solutions manual and set of viewgraphs for use in lectures are available for instructors, from [email protected].

The theoretical basis and the relevant experimental knowledge underlying our present understanding of the electrical and optical properties of semiconductor heterostructures. Although such structures have been known since the 1940s, it was only in the 1980s that they moved to the forefront of research. The resulting structures have remarkable properties not shared by bulk materials. The text begins with a description of the electronic properties of various types of heterostructures, including discussions of complex band-structure effects, localised states, tunnelling phenomena, and excitonic states. The focus of the remainder of the book is on optical properties, including intraband absorption, luminescence and recombination, Raman scattering, subband optical transitions, nonlinear effects, and ultrafast optical phenomena. The concluding chapter presents an overview of some of the applications that make use of the physics discussed. Appendices provide background information on band structure theory, kinetic theory, electromagnetic modes, and Coulomb effects.