Two topics in the forefront of superconductor research--superconductor-insulator transition in thin films and vortex tunneling in granular, bulk, and high temperature superconductors--have never before been given a unified and deductive treatment. This monograph and text provides a much-needed, comprehensive introduction to the theory of quantum fluctuations in inhomogenous superconducting materials. It be will be of great use to students and researchers in disciplines such as superconductivity, many-body systems, phase transitions, submicron physics, and surface science.

Infrared and Millimeter Waves, Volume 13: Millimeter Components and Techniques, Part IV compiles the work of several authors while focusing on certain aspects of infrared and millimeter waves, such as sources of radiation, instrumentation, and millimeter systems. This volume covers millimeter components and techniques. This text first covers the use of powerful gyrotrons for thermonuclear research, and then discusses high-power coherent radiation sources. Kinetic theory of harmonic gyrotron oscillator with slotted resonant structure is the focus of Chapter 3, while integrated fin-line components for communication, radar, and radiometer applications is the subject of Chapter 4. The fifth chapter discusses propagation and mode coupling in corrugated and smooth-wall circular waveguides. Chapter 6 discusses far-infrared properties of inhomogeneous materials, and the last chapter covers solid-state spectroscopy with far-infrared continuous-wave lasers. This book will be of great use to researchers or professionals whose work involves infrared and millimeter waves.

Since the discovery of superconductivity in 1911 by H. Kamerlingh Onnes, of the order of half a billion dollars has been spent on research directed toward understanding and utiliz ing this phenomenon. This investment has gained us fundamental understanding in the form of a microscopic theory of superconduc tivity. Moreover, superconductivity has been transformed from a laboratory curiosity to the basis of some of the most sensitive and accurate measuring devices known, a whole host of other elec tronic devices, a soon-to-be new international standard for the volt, a prototype generation of superconducting motors and gener ators, and magnets producing the highest continuous magnetic fields yet produced by man. The promise of more efficient means of power transmission and mass transportation, a new generation of superconducting motors and generators, and computers and other electronic devices with superconducting circuit elements is all too clear. The realization of controlled thermonuclear fusion is perhaps totally dependent upon the creation of enormous magnetic fields over large volumes by some future generation of supercon ducting magnets. Nevertheless, whether or not the technological promise of superconductivity comes to full flower depends as much, and perhaps more, upon economic and political factors as it does upon new technological and scientific breakthroughs. The basic science of superconductivity and its technological implications were the subject of a short course on "The Science and Technology of Superconductivity" held at Georgetown University, Washington, D. C. , during 13-26 August 1971.

The motto of connectivity and superconductivity is that the solutions of the Ginzburg–Landau equations are qualitatively in?uenced by the topology of the boundaries. Special attention is given to the “zero set”,the set of the positions (usually known as “quantum vortices”) where the order parameter vanishes. The paradigm of connectivity and superconductivity is the Little– Parks e?ect,discussed in most textbooks on superconductivity. This volume is intended to serve as a reference book for graduate students and researchers in physics or mathematics interested in superconductivity, or in the Schr ̈ odinger equation as a limiting case of the Ginzburg–Landau equations. The e?ects considered here usually become important in the regime where the coherence length is of the order of the dimensions of the sample. While in the Little–Parks days a lot of ingenuity was required to achieve this regime, present microelectronic techniques have transformed it into a routine. Mo- over,measurement and visualization techniques are developing at a pace which makes it reasonable to expect veri?cation of distributions,and not only of global properties. Activity in the ?eld has grown and diversi?ed substantially in recent years. We have therefore invited experts ranging from experimental and theoretical physicists to pure and applied mathematicians to contribute articles for this book. While the skeleton of the book deals with superconductivity,micron- works and generalizations of the Little–Parks situation,there are also articles which deal with applications of the Ginzburg–Landau formalism to several fundamental topics,such as quantum coherence,cosmology,and questions in materials science.