Realizing Controllable Quantum States - Proceedings Of The International Symposium On Mesoscopic Superconductivity And Spintronics - In The Light Of Quantum Computation


Book Description

This volume is a collection of papers from the third meeting of the international symposium on mesoscopic superconductivity and spintronics. Research on quantum information technology has advanced a great deal since the previous meeting. Mesoscopic physics, such as spins in nano-scale semiconductor structures, micro-fabricated superconducting junctions and extraordinary metal contacts have now been not only theoretically but also experimentally established as important solid-state elements of quantum information devices. The book also contains some papers on information theory from the viewpoint of quantum algorithms, indicating that further collaboration between physics and computer science promises to produce fruitful results in quantum information technology.




Controllable Quantum States


Book Description

This volume is a collection of papers from the fourth meeting of the International Symposium on Mesoscopic Superconductivity and Spintronics held at NTT Atsugi, Japan. Research in these fields has advanced a great deal since the previous meeting, largely because these fields have drawn much attention from the viewpoint of new quantum phenomena and quantum information technology. Mesoscopic superconductivity has been developed in new fields, such as a ferromagnet/superconductor junction, the proximity effect in unconventional superconductors, macroscopic quantum tunneling in high-Tc superconductors, quantum modulation of superconducting junctions and superconducting quantum bits. The book also covers transport and spins in nano-scale semiconductor structures such as quantum dots and wires, quantum interference and coherence and order in exotic materials, and some papers on quantum algorithm. This book adequately provides an overview of recent progress in mesoscopic superconductivity.




Controllable Quantum States: Mesoscopic Superconductivity And Spintronics (Ms+s2006) - Proceedings Of The International Symposium


Book Description

This volume is a collection of papers from the fourth meeting of the International Symposium on Mesoscopic Superconductivity and Spintronics held at NTT Atsugi, Japan. Research in these fields has advanced a great deal since the previous meeting, largely because these fields have drawn much attention from the viewpoint of new quantum phenomena and quantum information technology. Mesoscopic superconductivity has been developed in new fields, such as a ferromagnet/superconductor junction, the proximity effect in unconventional superconductors, macroscopic quantum tunneling in high-Tc superconductors, quantum modulation of superconducting junctions and superconducting quantum bits. The book also covers transport and spins in nano-scale semiconductor structures such as quantum dots and wires, quantum interference and coherence and order in exotic materials, and some papers on quantum algorithm. This book adequately provides an overview of recent progress in mesoscopic superconductivity.




Communication Shock


Book Description

In the spirit of Alvin Toffler’s acclaimed works peering into the future of the technological society, Communication Shock is a concise history of communication technologies and an exploration of the possible social and human impacts of nanotechnology on the ecology of human communication. As we become increasingly more networked with communication technologies, we must come to understand and confront the social impact of these changes. More importantly, we must wisely choose in embracing or rejecting these technologies and exploring how we might do both by striking an appropriate balance. Grounded in communication theory and praxis, Communication Shock brings some objectivity to the discussion of technology, maps its development, and encourages a rational conversation about its potential problems and promise. It challenges readers to reach their own conclusions – about the future, imagined and unimaginable, about the fundamental values in conflict, and how one might choose to embrace or contest them to maintain individual autonomy in the face of increasingly ubiquitous marketing and technological change. Present and emerging communications technologies hold the promise for a bold new future, but they also have their inherent risks and drawbacks. Communication shock is the human response, conscious or unconscious, wherein the individual chooses to resist the growing pervasiveness of technology in his or her life by seeking ways to reduce or redirect new technologies or to reject the addition of such technologies altogether. Here is a framework for understanding the potential of the evolving technologies, determining which are essential and which are distractions from the life that one believes to be meaningful, and making informed choices for the life one wishes to live.




Quantum Machine Learning


Book Description

This book presents a new way of thinking about quantum mechanics and machine learning by merging the two. Quantum mechanics and machine learning may seem theoretically disparate, but their link becomes clear through the density matrix operator which can be readily approximated by neural network models, permitting a formulation of quantum physics in which physical observables can be computed via neural networks. As well as demonstrating the natural affinity of quantum physics and machine learning, this viewpoint opens rich possibilities in terms of computation, efficient hardware, and scalability. One can also obtain trainable models to optimize applications and fine-tune theories, such as approximation of the ground state in many body systems, and boosting quantum circuits’ performance. The book begins with the introduction of programming tools and basic concepts of machine learning, with necessary background material from quantum mechanics and quantum information also provided. This enables the basic building blocks, neural network models for vacuum states, to be introduced. The highlights that follow include: non-classical state representations, with squeezers and beam splitters used to implement the primary layers for quantum computing; boson sampling with neural network models; an overview of available quantum computing platforms, their models, and their programming; and neural network models as a variational ansatz for many-body Hamiltonian ground states with applications to Ising machines and solitons. The book emphasizes coding, with many open source examples in Python and TensorFlow, while MATLAB and Mathematica routines clarify and validate proofs. This book is essential reading for graduate students and researchers who want to develop both the requisite physics and coding knowledge to understand the rich interplay of quantum mechanics and machine learning.




Length-Scale Dependent Phonon Interactions


Book Description

This book presents a comprehensive description of phonons and their interactions in systems with different dimensions and length scales. Internationally-recognized leaders describe theories and measurements of phonon interactions in relation to the design of materials with exotic properties such as metamaterials, nano-mechanical systems, next-generation electronic, photonic, and acoustic devices, energy harvesting, optical information storage, and applications of phonon lasers in a variety of fields. The emergence of techniques for control of semiconductor properties and geometry has enabled engineers to design structures in which functionality is derived from controlling electron behavior. As manufacturing techniques have greatly expanded the list of available materials and the range of attainable length scales, similar opportunities now exist for designing devices whose functionality is derived from controlling phonon behavior. However, progress in this area is hampered by gaps in our knowledge of phonon transport across and along arbitrary interfaces, the scattering of phonons with crystal defects, interface roughness and mass-mixing, delocalized electrons/collective electronic excitations, and solid acoustic vibrations when these occur in structures with small physical dimensions. This book provides a comprehensive description of phonons and their interactions in systems with different dimensions and length scales. Theories and measurements of phonon interactions are described in relation to the design of materials with exotic properties such as metamaterials, nano-mechanical systems, next-generation electronic, photonic, and acoustic devices, energy harvesting, optical information storage, and applications of phonon lasers in a variety of fields.




Quantum Computers, Algorithms and Chaos


Book Description

During the last ten years Quantum Information Processing and Communication (QIPC) has established itself as one of the new hot topic fields in physics, with the potential to revolutionize many areas of science and technology. QIPC replaces the laws of classical physics applied to computation and communication with the more fundamental laws of quantum mechanics. This becomes increasingly important due to technological progress going down to smaller and smaller scales where quantum effects start to be dominant. In addition to its fundamental nature, QIPC promises to advance computing power beyond the capabilities of any classical computer, to guarantee secure communication and establish direct links to emerging quantum technologies, such as, for example, quantum based sensors and clocks. One of the outstanding feature of QIPC is its interdisciplinary character: it brings together researchers from physics, mathematics and computer science. In particular, within physics we have seen the emergence of a new QIPC community, which ranges from theoretical to experimental physics, and crosses boundaries of traditionally separated disciplines such as atomic physics, quantum optics, statistical mechanics and solid state physics, all working on different and complementary aspects of QIPC. This publication covers the following topics: Introduction to quantum computing; Quantum logic, information and entanglement; Quantum algorithms; Error-correcting codes for quantum computations; Quantum measurements and control; Quantum communication; Quantum optics and cold atoms for quantum information; Quantum computing with solid state devices; Theory and experiments for superconducting qubits; Interactions in many-body systems: quantum chaos, disorder and random matrices; Decoherence effects for quantum computing; and Flature prospects of quantum information processing.




Towards the Controllable Quantum States


Book Description

The realizations of physical systems whose quantum states can be directly manipulated have been pursued for experiments on fundamental problems in quantum mechanics and implementations of quantum information devices. Micro-fabricated superconducting systems and electronic spins are among the most promising candidates. This book contains the newest and most advanced research reports on such materials, called ?Mesoscopic Superconductivity? and ?Spintronics?. The former includes superconductor-semiconductor hybrid systems, very small Josephson junctions, and micron-size SQUIDs. The latter includes the control of spin transports in semiconductor heterostructures, nano-scale quantum dots, and spin injections. Superconductor-ferromagnetic metal hybrid structures are covered by both of the topics.The proceedings have been selected for coverage in: ? Index to Scientific & Technical Proceedings (ISTP CDROM version / ISI Proceedings)




Control of Quantum Systems


Book Description

Advanced research reference examining the closed and open quantum systems Control of Quantum Systems: Theory and Methods provides an insight into the modern approaches to control of quantum systems evolution, with a focus on both closed and open (dissipative) quantum systems. The topic is timely covering the newest research in the field, and presents and summarizes practical methods and addresses the more theoretical aspects of control, which are of high current interest, but which are not covered at this level in other text books. The quantum control theory and methods written in the book are the results of combination of macro-control theory and microscopic quantum system features. As the development of the nanotechnology progresses, the quantum control theory and methods proposed today are expected to be useful in real quantum systems within five years. The progress of the quantum control theory and methods will promote the progress and development of quantum information, quantum computing, and quantum communication. Equips readers with the potential theories and advanced methods to solve existing problems in quantum optics/information/computing, mesoscopic systems, spin systems, superconducting devices, nano-mechanical devices, precision metrology. Ideal for researchers, academics and engineers in quantum engineering, quantum computing, quantum information, quantum communication, quantum physics, and quantum chemistry, whose research interests are quantum systems control.




Advanced Quantum Communications


Book Description

The book provides an overview of the most advanced quantum informational geometric techniques, which can help quantum communication theorists analyze quantum channels, such as security or additivity properties. Each section addresses an area of major research of quantum information theory and quantum communication networks. The authors present the fundamental theoretical results of quantum information theory, while also presenting the details of advanced quantum ccommunication protocols with clear mathematical and information theoretical background. This book bridges the gap between quantum physics, quantum information theory, and practical engineering.