Electron tunnelling spectroscopy as a research tool has strongly advanced understanding of superconductivity. This book explains the physics and instrumentation behind the advances illustrated in beautiful images of atoms, rings of atoms and exotic states in high temperature superconductors, and summarizes the state of knowledge that has resulted.

This book provides a comprehensive and up-to-date treatment of solid state electron tunneling phenomena, with emphasis on their systematic application in junction devices to probe electronic and vibrational properties of superconductors, normal metals, semiconductors, and thin insulating barrier layers. The quantum-mechanical foundations of the subject are traced, and the most active areas of tunneling research are covered in a uniform and coherent manner. A thorough treatment of experimental techniques in tunneling research is provided, along with an introduction to the relevant techniques of data analysis.

Inelastic Electron Tunneling Spectroscop~ or lETS, provides a unique technique for electronically monitoring the vibrational modes of molecul (;5 adsorbed on a metal oxide surface. Since the discovery of the phenomena by JAKLEVIC and LM1BE in 1966, lETS has been developed by a number of scientists as a method for studying the surface chemistry of molecular species adsorbed on aluminum oxide. Recent applications of lETS include investigations of physical and chemical adsorption of hydrocarbons, studies of catalysis by metal particles, detection and identification of trace substances in air and water, and studies of biological molecules and electron damage to such molecules. lETS has been employed to investigate adhesive materials, and studies are currently in prog ress to investigate corrosion species and corrosion inhibitors on aluminum and its alloys. Electronic transitions of molecules have also been studied by lETS. The recent development of the "external doping" technique, whereby molecu lar species can be introduced into fabricated tunnel junctions, opens the door for a vast new array of surface chemical studies by lETS. lETS is rap idly becoming an important tool for the study of surface and interface phe nomena. In addition to its role in surface studies, inelastic tunneling has proved extremely valuable for the study of the electronic properties of thin metallic films, and the recent discovery of light emission from inelastic tunneling promises to be of some importance in the area of device physics.

This book has been compiled to give specialists, in areas that could be helped by tunneling spectroscopy, a rounded and relatively painless intro duction to the field. Why relatively painless? Because this book is filled with figures-A quick glance through these figures can give one a good idea of the types of systems that can be studied and the quality of results that can be obtained. To date, it has been somewhat difficult to learn about tunneling spectroscopy, as papers in this field have appeared in a diversity of scientific journals: for example. The Journal of Adhesion, J(}urnal (}f Catalysis, Surface and Interface Analysis, Science, Journal of the American Chemical Society, Physical Review-over 45 different ones in all, plus numerous conference proceedings. This diversity is, however, undoubtedly healthy. It indicates that the findings of tunneling spectroscopy are of interest and potential benefit to a wide audience. This book can help people who have seen a few papers or heard a talk on tunneling spectroscopy and want to learn more about what it can do for their field. Tunneling spectroscopy is presently in a transitional state. Its experi mental methods and theoretical basis have been reasonably well developed. Its continued vitality will depend on the success of its applications. Crucial to that success, as pointed out by Ward Plummer, is the adoption of tunneling spectroscopy by specialists in the areas of application.