"This volume gives an overview of the manifestations of quantum coherence in different solid state systems, including semiconductor confined systems, magnetic systems, crystals and superconductors. Besides being of paramount importance in fundamental physics, the study of quantum coherence furnishes the starting point for important applications like quantum computing or secure data transmission. The coherent effects discussed mainly involve elementary excitations in solids like polaritons, excitons, magnons, macroscopic quantities like superconductor currents and electron spins. Also, several new aspects of the physics of quasi-particles are understood and discussed in this context. Due to the variety of systems in which quantum coherence may be observed, solid state systems are the natural candidates for applications that rely on coherence, for example quantum computer." --Book Jacket.

This book features the proceedings of the NATO Advanced Study Institute "Manipulating Quantum Coherence in Solid State Systems", held in Cluj-Napoca, Romania, August 2005, which presented a fundamental introduction to solid-state approaches to achieving quantum computation. This proceedings volume describes the properties of quantum coherence in semiconductor spin-based systems and the behavior of quantum coherence in superconducting systems.

Quantum Computation in Solid State Systems discusses experimental implementation of quantum computing for information processing devices; in particular observations of quantum behavior in several solid state systems are presented. The complementary theoretical contributions provide models of minimizing decoherence in the different systems. Most recent theoretical and experimental results on macroscopic quantum coherence of mesoscopic systems, as well as the realization of solid-state qubits and quantum gates are discussed. Particular attention is given to coherence effects in Josephson devices. Other solid state systems---including quantum dots, optical, ion, and spin devices---are also discussed.

This volume is an outgrowth of the Second International Workshop on Macroscopic Quantum Coherence and Computing held in Napoli, Italy, in June 2000. This workshop gathered a number of experts from the major Universities and Research Institutions of several countries. The choice of the location, which recognizes the role and the traditions of Naples in this field, guaranteed the participants a stimulating atmosphere. The aim of the workshop has been to report on the recent theoretical and experimental results on the macroscopic quantum coherence of macroscopic systems. Particular attention was devoted to Josephson devices. The correlation with other atomic and molecular systems, exhibiting a macroscopic quantum behaviour, was also discussed. The seminars provided both historical overview and recent theoretical ground on the topic, as well as information on new experimental results relative to the quantum computing area. The first workshop on this topic, held in Napoli in 1998, has been ennobled by important reports on observations of Macroscopic Quantum Coherence in mesoscopic systems. The current workshop proposed, among many stimulating results, the first observations of Macroscopic Quantum Coherence between macroscopically distinct fluxoid states in rf SQUIDs, 20 years after the Leggett's proposal to experimentally test the quantum behavior of macroscopic systems. Reports on observations of quantum behaviour in molecular and magnetic systems, small Josephson devices, quantum dots have also been particularly stimulating in view of the realization of several possible q-bits.

Dedicated to the memory of Franco Bassani, the former President of the Societa Italiana di Fisica, this volume gives an overview of the manifestations of quantum coherence in different solid state systems, including semiconductor confined systems, magnetic systems, crystals and superconductors.

Starting from first principles, this book introduces the fundamental concepts and methods of dissipative quantum mechanics and explores related phenomena in condensed matter systems. Major experimental achievements in cooperation with theoretical advances have brightened the field and brought it to the attention of the general community in natural sciences. Nowadays, working knowledge of dissipative quantum mechanics is an essential tool for many physicists. This book -- originally published in 1990 and republished in 1999 and and 2008 as enlarged second and third editions -- delves significantly deeper than ever before into the fundamental concepts, methods and applications of quantum dissipative systems.This fourth edition provides a self-contained and updated account of the quantum mechanics of open systems and offers important new material including the most recent developments. The subject matter has been expanded by about fifteen percent. Many chapters have been completely rewritten to better cater to both the needs of newcomers to the field and the requests of the advanced readership. Two chapters have been added that account for recent progress in the field. This book should be accessible to all graduate students in physics. Researchers will find this a rich and stimulating source.

Ever since 1911, the Solvay Conferences have shaped modern physics. The 25th edition held in October 2011 in Brussels and chaired by David Gross continued this tradition and celebrated the first centennial of this illustrious series of conferences. The development and applications of quantum mechanics have always been the main threads in the history of the Solvay Conferences, hence the 25th Solvay conference gathered many of the leading figures working on a wide variety of profound problems in physics where quantum mechanical effects play a central role. The conference addressed some of the most pressing open questions in the field of physics.The proceedings contain the “rapporteur talks” which give a broad overview with unique insights by distinguished and renowned scientists. These lectures cover the seven sessions: “History and Reflections”, “Foundations of Quantum Mechanics and Quantum Computation”, “Control of Quantum Systems”, “Quantum Condensed Matter”, “Particles and Fields”, “Quantum Gravity and String Theory” and it ended with a general discussion attempting to arrive at a synthesis.In the Solvay tradition, the proceedings also include the prepared comments to the rapporteur talks. The discussions among the participants — some of which quite lively and involving dramatically divergent points of view — have been carefully edited and are reproduced in full.

The results of the research re-ported in this work show that tunable gap flux qubits have a potential for building quantum registers. Cavities coupled to flux qubits can be used for in-formation storage and transfer between qubits. SFS π-shifters provide a simple approach to bias multi-qubit circuits. A possibility to change the qubit resonance frequency while preserving qubit coherence enables implementation of switchable coupling between qubits and cavities.

This book features the proceedings of the NATO Advanced Study Institute "Manipulating Quantum Coherence in Solid State Systems", held in Cluj-Napoca, Romania, August 2005, which presented a fundamental introduction to solid-state approaches to achieving quantum computation. This proceedings volume describes the properties of quantum coherence in semiconductor spin-based systems and the behavior of quantum coherence in superconducting systems.

Magnetism encompasses a wide range of systems and physical phenomena, and its study has posed and exposed both important fundamental problems and many practical applications. Recently, several entirely new phenomena have thus been discovered, generated through cooperative behaviour which could not have been predicted from a knowledge of `one-spin' states. At the same time, advances in sample preparation, experimental technique, apparatus and radiation sources, have led to increasing precision in the investigation and exposure of greater subtleties in magnetic thin films, multilayers and other systems. Examples of unexpected and conceptually new phenomena occur in strongly correlated and fluctuating quantum systems, producing effects such as Haldane and spin-Peierls gaps, solitons, quantum spin glasses and spin liquids. The discovery and elucidation of these `emerging properties' is a central theme in modern condensed matter physics. The present book comprises a series of chapters by world experts, covering both theoretical and experimental aspects. The approach is pedagogical and tutorial, but fully up to date, covering the latest research. The level is appropriate to graduate researchers who may either be just moving into the field or who are already active in condensed matter physics.