This book highlights novel research work done on cold atom-based quantum networks. Given that one of the main challenges in building the quantum network is the limited entanglement distribution distance, this book presents some state-of-the-art experiments in tackling this challenge and, for the first time, establishes entanglement between quantum memories via metropolitan-scale fiber transmission. This achievement is accomplished by cooperating high-efficiency cold quantum memories, low-loss quantum frequency conversion modules, and long-fiber phase-locking techniques. In the book, the scheme design, experimental setup, data analyses, and numerous technical details are given. Therefore, it suits a broad readership that includes all students, researchers, and technicians who work in quantum information sciences.

Photonic Quantum Technologies Brings together top-level research results to enable the development of practical quantum devices In Photonic Quantum Technologies: Science and Applications, the editor Mohamed Benyoucef and a team of distinguished scientists from different disciplines deliver an authoritative, one-stop overview of up-to-date research on various quantum systems. This unique book reviews the state-of-the-art research in photonic quantum technologies and bridges the fundamentals of the field with applications to provide readers from academia and industry, in one-location resource, with cutting-edge knowledge they need to have to understand and develop practical quantum systems for application in e.g., secure quantum communication, quantum metrology, and quantum computing. The book also addresses fundamental and engineering challenges en route to workable quantum devices and ways to circumvent or overcome them. Readers will also find: A thorough introduction to the fundamentals of quantum technologies, including discussions of the second quantum revolution (by Nobel Laureate Alain Aspect), solid-state quantum optics, and non-classical light and quantum entanglement Comprehensive explorations of emerging quantum technologies and their practical applications, including quantum repeaters, satellite-based quantum communication, quantum networks, silicon quantum photonics, integrated quantum systems, and future vision Practical discussions of quantum technologies with artificial atoms, color centers, 2D materials, molecules, atoms, ions, and optical clocks Perfect for molecular and solid-state physicists, Photonic Quantum Technologies: Science and Applications will also benefit industrial and academic researchers in photonics and quantum optics, graduate students in the field; engineers, chemists, and computer and material scientists.

This thesis presents an experimental study of quantum memory based on cold atomic ensembles and discusses photonic entanglement. It mainly focuses on experimental research on storing orbital angular momentum, and introduces readers to methods for storing a single photon carried by an image or an entanglement of spatial modes. The thesis also discusses the storage of photonic entanglement using the Raman scheme as a step toward implementing high-bandwidth quantum memory. The storage of photonic entanglement is central to achieving long-distance quantum communication based on quantum repeaters and scalable linear optical quantum computation. Addressing this key issue, the findings presented in the thesis are very promising with regard to future high-speed and high-capacity quantum communications.

This book highlights the novel research in quantum memory networking, especially quantum memories based on cold atomic ensembles. After discussing the frontiers of quantum networking research and building a DLCZ-type quantum memory with cold atomic ensemble, the author develops the ring cavity enhanced quantum memory and demonstrates a filter-free quantum memory, which significantly improves the photon-atom entanglement. The author then realizes for the first time the GHZ-type entanglement of three separate quantum memories, a building block of 2D quantum repeaters and quantum networks. The author also combines quantum memories and time-resolved measurements, and reports the first multiple interference of three single photons with different colors. The book is of good reference value for graduate students, researchers, and technical personnel in quantum information sciences.

This book traces the evolution of our understanding and utilization of light from classical antiquity and the early thoughts of Pythagoras to the present time. From the earliest recorded theories and experiments to the latest applications in photonic communication and computation, the ways in which light has been put to use are numerous and astounding. Indeed, some of the latest advances in light science are in fields that until recently belonged to the realm of science fiction. The author, writing for an audience of both students and other scientifically interested readers, describes fundamental investigations of the nature of light and ongoing methods to measure its speed as well as the emergence of the wave theory of light and the complementary photon theory. The importance of light in the theory of relativity is discussed as is the development of electrically-driven light sources and lasers. The information here covers the range o f weak single-photon light sources to super-high power lasers and synchrotron light sources. Many cutting-edge topics are also introduced, including entanglement-based quantum communication through optical fibers and free space, quantum teleportation, and quantum computing. The nature and use of "squeezed light" - e.g. for gravitational wave detection - is another fascinating excursion, as is the topic of fabricated metamaterials, as used to create invisibility cloaks. Here the reader also learns about the realization of extremely slow speed and time-reversed light. The theories, experiments, and applications described in this book are, whenever possible, derived from original references. The many annotated drawings and level of detail make clear the goals, procedures, and conclusions of the original investigators. Where they are required, all specialist terms and mathematical symbols are defined and explained. The final part of the book covers light expe riments in the free space of the cosmos, and also speculates about scenarios for the cosmological origins of light and the expected fate of the photon in a dying universe.

This book sheds light on the fundamental and innovative topics in information systems and their societal impact on individuals and organizations. It mainly focuses on the role of artificial intelligence in organizations, human-computer interaction, IS in education and industry, and IS security, privacy, and trust. The outcomes are expected to assist the decision-makers in formulating the required policies and procedures for using cutting-edge technologies.

Quantum Continuous Variables introduces the theory of continuous variable quantum systems, from its foundations based on the framework of Gaussian states to modern developments, including its applications to quantum information and forthcoming quantum technologies. This new book addresses the theory of Gaussian states, operations, and dynamics in great depth and breadth, through a novel approach that embraces both the Hilbert space and phase descriptions. The volume includes coverage of entanglement theory and quantum information protocols, and their connection with relevant experimental set-ups. General techniques for non-Gaussian manipulations also emerge as the treatment unfolds, and are demonstrated with specific case studies. This book will be of interest to graduate students looking to familiarise themselves with the field, in addition to experienced researchers eager to enhance their understanding of its theoretical methods. It will also appeal to experimentalists searching for a rigorous but accessible treatment of the theory in the area.

The first industrial revolution was accompanied by the emergence of the School of Engineering, the second brought about the School of Electrical Engineering, and the third digital revolution led to the School of Information. It is now obvious that the change in this quantum revolution must lead to the emergence of the School of Quantum Science and Technology. Quantum technology can develop comprehensively through the integration of science, technology, engineering, art and mathematics (STEAM). In 1925, Heisenberg developed the Matrix Mechanics, cracking the mysteries of the Quantum world. Coinciding with the 100th anniversary of Matrix Mechanics, in 2024, the General Assembly of the United Nations proclaimed 2025 the 'International Year of Quantum Science and Technology,' along with a year-long initiative celebrating the profound impacts of quantum science on technology, culture, and our understanding of the natural world.This book outlines the importance of the 'Second Quantum Revolution,' introduces quantum computers, quantum communications, and quantum sensors, and then provides a framework for the emergence of the quantum Internet of Things. What basic quantum literacy should modern citizens have in this era? The 'Second Quantum Revolution,' where quantum knowledge and engineering technology are once again combined, will provide faster, more effective, and more sensitive quantum facilities to accelerate cross-field exploration, and will also make human life more comfortable and convenient than ever before.In the 'First Quantum Revolution' in the 20th century, humans learned quantum science from nature and used existing materials to make quantum components. In the 'Second Quantum Revolution' in the 21st century, humans further used quantum science to construct quantum engineering. We now make materials and components that are not found in nature and assemble new quantum machines to benefit mankind! This is the stage of a glorious quantum era, which is a hundred times more brilliant than the past classical physics era.

After laying the foundation by explaining the fundamental principles of light propagation and optical resonators, this book delves into the realm of implementing resonators through a fiber-based approach. It extensively explores fiber-based resonators, encompassing a comprehensive discussion spanning from their intricacies of design to their pivotal roles in advancing quantum optics experiments. Furthermore, it details the design techniques, meticulously explaining the latest developments within this dynamic field. There are vivid illustrations highlighting the various applications of resonators in experimental optics and cavity quantum electrodynamics. Also, a discourse is presented regarding the future potential of fiber-based resonators in quantum technology. The book serves as a valuable resource for individuals with an interest in optical resonators and their boundless possibilities.

Quantum information processing offers fundamental improvements over classical information processing, such as computing power, secure communication, and high-precision measurements. However, the best way to create practical devices is not yet known. This textbook describes the techniques that are likely to be used in implementing optical quantum information processors. After developing the fundamental concepts in quantum optics and quantum information theory, the book shows how optical systems can be used to build quantum computers according to the most recent ideas. It discusses implementations based on single photons and linear optics, optically controlled atoms and solid-state systems, atomic ensembles, and optical continuous variables. This book is ideal for graduate students beginning research in optical quantum information processing. It presents the most important techniques of the field using worked examples and over 120 exercises.