Quantum communication is a field of applied quantum physics closely related to quantum information processing and quantum teleportation. Quantum information science (QIS) [ 1 ] has been evolving rapidly in recent years in terms of quantum communications and quantum computing (QC). Its most interesting application is protecting information channels against eavesdropping by means of quantum cryptography. It is envisioned that QIS will enable and boost future 6G systems from both communication and computing perspectives. For example, secure quantum communications such as quantum key distribution (QKD) can be leveraged to improve 6G security. QIS mainly consists of four branches: quantum mechanics, QC, quantum communications, and quantum sensing (QS) and metrology. However, Quantum mechanics provides the theoretical foundations and building blocks for quantum communications, QC, and QS and metrology, as depicted in Figure 25.1 .
Quantum communication is a field of applied quantum physics closely related to quantum information processing and quantum teleportation. Quantum information science (QIS) [ 1 ] has been evolving rapidly in recent years in terms of quantum communications and quantum computing (QC). Its most interesting application is protecting information channels against eavesdropping by means of quantum cryptography. It is envisioned that QIS will enable and boost future 6G systems from both communication and computing perspectives. For example, secure quantum communications such as quantum key distribution (QKD) can be leveraged to improve 6G security. QIS mainly consists of four branches: quantum mechanics, QC, quantum communications, and quantum sensing (QS) and metrology. However, Quantum mechanics provides the theoretical foundations and building blocks for quantum communications, QC, and QS and metrology, as depicted in Figure 25.1 .
Quantum information science (QIS) explores how information can be encoded, processed, and transmitted using the principles of quantum mechanics. Quantum technologies including quantum computing, quantum communication, and quantum sensing have experienced rapid advancements over the past decade. This review highlights foundational concepts, major technological platforms, applications, and current research trends. It also examines challenges in scalability, error correction, and implementation that shape the pathway toward practical quantum systems.
Abstract In the technologically changing world, the demand for ultra‐reliable, faster, low power, and secure communication has significantly risen in recent years. Researchers have shown immense interest in emerging quantum computing (QC) due to its potentials of solving the computing complexity in the robust and efficient manner. It is envisioned that QC can act as critical enablers and strong catalysts to considerably reduce the computing complexities and boost the future of sixth generation (6G) and beyond communication systems in terms of their security. In this study, the fundamentals of QC, the evolution of quantum communication that encompasses a wide spectrum of technologies and applications and quantum key distribution, which is one of the most promising applications of quantum security, have been presented. Furthermore, various parameters and important techniques are also investigated to optimise the performance of 6G communication in terms of their security, computing, and communication efficiency. Towards the end, potential challenges that QC and quantum communication may face in 6G have been highlighted along with future directions.
This chapter discusses quantum information science (QIS), quantum key distribution (QKD), and quantum teleportation. The new field of QIS encompasses several overlapping subdisciplines: quantum computing, quantum key distribution (also known as quantum cryptography), and quantum metrology (the measurement of small parameters and weak forces with ultra-high precision). In QIS, bits of information are encoded in quantum states, which themselves can be in superposition states and/or entanglement states. Generically, the 0 and 1 quantum bits are represented as qubits (quantum bits). QKD, or quantum cryptography, is a completely secure method of secret communication, and will remain so even if a quantum computer becomes available. Quantum teleportation is one of the more exotic features to have emerged from the field of QIS. It refers to the ability to transfer an unknown quantum state from one location to another, possibly very distant, location by using quantum entanglement.
Quantum communication is a rapidly evolving field that leverages quantum physics to enable secure and efficient information exchange. A cornerstone of quantum cryptography is Quantum Key Distribution (QKD), a secure key exchange mechanism that ensures the confidentiality of transmitted data by employing the no-cloning theorem and the uncertainty principle of quantum mechanics. This study explores key aspects of quantum networks and communication, including quantum states, QKD, and quantum cryptographic protocols, with a focus on photon polarization states and entangled qubits as fundamental building blocks of quantum information. Additionally, two well-established quantum cryptographic protocols, BB84 and E91, are analyzed for their principles and advantages in secure communication. However, challenges such as quantum state loss in communication channels hinder the long-distance transmission of quantum information. To address these issues, error detection, measurement, and correction techniques are investigated, with quantum error correction methods playing a crucial role in mitigating noise and imperfections, ensuring accurate quantum information transmission, and enhancing the overall efficiency of quantum communication systems. Beyond conventional networks, quantum communication holds vast potential for cybersecurity applications, paving the way for next-generation secure communication frameworks.
In order to provide novel techniques for processing, storing, and transmitting information, the multidisciplinary field of quantum information science (QIS) integrates ideas from quantum physics [ 4 ] with information science. However, due to a number of events, including Peter Shor’s invention of quantum algorithms and the rise in interest in quantum computing, the history of QIS started to expand quickly in the early to middle 1990s. Peter Shor, a physicist and mathematician, developed the first quantum algorithm that could factor big numbers exponentially more rapidly than any classical algorithm in 1994. This finding triggered strong interest in quantum computing’s potential to tackle issues that are currently unsolvable for classical computers. Since then, QIS has advanced due to the development of novel quantum algorithms and enhancements in the hardware used for quantum computing. Understanding complex quantum phenomena like entanglement and superposition and developing novel strategies for utilizing them for information processing and communication are the core goals of QIS. Quantum bits (qubits) can exist in superpositions of 0 and 1 simultaneously, which enables far more efficient computation than classical bits, which can only be in one state or the other at a given time. Superposition is a key concept in quantum computing. In addition to superposition, entanglement, coherence, and quantum algorithms are other important QIS concepts. Entanglement is a key feature of quantum mechanics and has been observed experimentally in a wide range of physical systems, including photons, atoms, and superconducting qubits. Two particles can get entangled with one another through a phenomenon called entanglement in which their quantum states exhibit a high correlation. This indicates that even if two particles are separated by a considerable distance, modifying the state of one can change the state of the other. No matter how far away two separate particles are from one another when they are entangled, measuring the state of one particle immediately gives the state of another particle. It plays a central role in many quantum technologies, including quantum computing for solving complex problems that take classical computers a long time to solve, quantum cryptography for secure communications, quantum sensing for quantum properties of particles to enable more precise measurements, and quantum networking to improve communication and processing speed over both short and long distances. Quantum metrology methods use the principles of quantum mechanics to improve the accuracy of measurements in fields like gravity sensors, timekeeping, and frequency standards. Some of the benefits of QIS are enhanced computing power, improved communication, advanced cryptography, more precise scientific measurements, and better logistics optimization.
Quantum entanglement, a fundamental phenomenon in quantum mechanics, has garnered significant attention for its potential to revolutionize communication systems. Unlike classical communication methods that rely on the transmission of information via classical signals, quantum communication leverages the principles of quantum mechanics, such as superposition and entanglement, to enable faster and more secure transmission of data. This paper explores the concept of quantum entanglement and its applications in next-generation communication systems, focusing on quantum key distribution (QKD), quantum teleportation, and quantum repeaters. We discuss the theoretical foundations, current advancements, challenges, and future directions in the integration of quantum entanglement into communication technologies. Keywords: Quantum Entanglement, Quantum Communication, Quantum Key Distribution (QKD), Quantum Teleportation, Quantum Networks, Quantum Repeaters, Quantum Cryptography, Quantum Internet, Secure Communication, Qubits, Entangled Particles, Quantum Security.