Quantum teleportation is a technique for transferring quantum information from a sender at one location to a receiver some distance away. While teleportation is commonly portrayed in science fiction as a means to transfer physical objects from one location to the next, quantum teleportation only transfers quantum information. The sender does not have to know the particular quantum state being transferred. Moreover, the location of the recipient can be unknown, but to complete the quantum teleportation, classical information needs to be sent from sender to receiver. Because classical information needs to be sent, quantum teleportation cannot occur faster than the speed of light.
Quantum entanglement is the phenomenon of a group of particles being generated, interacting, or sharing spatial proximity in such a way that the quantum state of each particle of the group cannot be described independently of the state of the others, including when the particles are separated by a large distance. The topic of quantum entanglement is at the heart of the disparity between classical and quantum physics: entanglement is a primary feature of quantum mechanics not present in classical mechanics.
Quantum key distribution (QKD) is a secure communication method that implements a cryptographic protocol involving components of quantum mechanics. It enables two parties to produce a shared random secret key known only to them, which then can be used to encrypt and decrypt messages. The process of quantum key distribution is not to be confused with quantum cryptography, as it is the best-known example of a quantum-cryptographic task.
Artur Konrad Ekert is a British-Polish professor of quantum physics at the Mathematical Institute, University of Oxford, professorial fellow in quantum physics and cryptography at Merton College, Oxford, Lee Kong Chian Centennial Professor at the National University of Singapore and the founding director of the Centre for Quantum Technologies (CQT). His research interests extend over most aspects of information processing in quantum-mechanical systems, with a focus on quantum communication and quantum computation. He is best known as one of the pioneers of quantum cryptography.
Quantum networks form an important element of quantum computing and quantum communication systems. Quantum networks facilitate the transmission of information in the form of quantum bits, also called qubits, between physically separated quantum processors. A quantum processor is a machine able to perform quantum circuits on a certain number of qubits. Quantum networks work in a similar way to classical networks. The main difference is that quantum networking, like quantum computing, is better at solving certain problems, such as modeling quantum systems.
In quantum optics, a NOON state or N00N state is a quantum-mechanical many-body entangled state:
Jonathan P. Dowling was an Irish-American researcher and professor in theoretical physics, known for his work on quantum technology, particularly for exploiting quantum entanglement for applications to quantum metrology, quantum sensing, and quantum imaging.
Quantum imaging is a new sub-field of quantum optics that exploits quantum correlations such as quantum entanglement of the electromagnetic field in order to image objects with a resolution or other imaging criteria that is beyond what is possible in classical optics. Examples of quantum imaging are quantum ghost imaging, quantum lithography, imaging with undetected photons, sub-shot-noise imaging, and quantum sensing. Quantum imaging may someday be useful for storing patterns of data in quantum computers and transmitting large amounts of highly secure encrypted information. Quantum mechanics has shown that light has inherent “uncertainties” in its features, manifested as moment-to-moment fluctuations in its properties. Controlling these fluctuations—which represent a sort of “noise”—can improve detection of faint objects, produce better amplified images, and allow workers to more accurately position laser beams.
Dipankar Home is an Indian theoretical physicist at Bose Institute, Kolkata. He works on the fundamental aspects of quantum mechanics, including quantum entanglement and Quantum communication. He is co-author with Partha Ghose of the popular book Riddles in your Teacup - Fun with Everyday Scientific Puzzles.
The International Conference on Physics of Light–Matter Coupling in Nanostructures (PLMCN) is a yearly academic conference on various topics of semiconductor science and nanophotonics.
Yoshihisa Yamamoto is the director of Physics & Informatics Laboratories, NTT Research, Inc. He is also Professor (Emeritus) at Stanford University and National Institute of Informatics (Tokyo).
Jeremy O'Brien is a physicist who researches in quantum optics, optical quantum metrology and quantum information science. He co-founded and is CEO of the quantum computing firm PsiQuantum. Formerly, he was Professorial Research Fellow in Physics and Electrical Engineering at the University of Bristol, and director of its Centre for Quantum Photonics.
Photonic molecules are a form of matter in which photons bind together to form "molecules". They were first predicted in 2007. Photonic molecules are formed when individual (massless) photons "interact with each other so strongly that they act as though they have mass". In an alternative definition, photons confined to two or more coupled optical cavities also reproduce the physics of interacting atomic energy levels, and have been termed as photonic molecules.
Nicolas Gisin is a Swiss physicist and professor at the University of Geneva, working on the foundations of quantum mechanics, quantum information, and communication. His work includes both experimental and theoretical physics. He has contributed work in the fields of experimental quantum cryptography and long-distance quantum communication over standard telecom optical fibers. He also co-founded ID Quantique, a company that provides quantum-based technologies.
Integrated quantum photonics, uses photonic integrated circuits to control photonic quantum states for applications in quantum technologies. As such, integrated quantum photonics provides a promising approach to the miniaturisation and scaling up of optical quantum circuits. The major application of integrated quantum photonics is Quantum technology:, for example quantum computing, quantum communication, quantum simulation, quantum walks and quantum metrology.
The six-state protocol (SSP) is the quantum cryptography protocol that is the version of BB84 that uses a six-state polarization scheme on three orthogonal bases.
Thomas Jennewein is an Austrian physicist who conducts research in quantum communication and quantum key distribution. He has taught as an associate professor at the University of Waterloo and the Institute for Quantum Computing in Waterloo, Canada since 2009. He earned his PhD under Anton Zeilinger at the University of Vienna in 2002, during which time he performed experiments on Bell's inequality and cryptography with entangled photons. His current work at the Institute for Quantum Computing focuses on satellite-based free space quantum key distribution, with the goal of creating a global quantum network.
A quantum dot single-photon source is based on a single quantum dot placed in an optical cavity. It is an on-demand single-photon source. A laser pulse can excite a pair of carriers known as an exciton in the quantum dot. The decay of a single exciton due to spontaneous emission leads to the emission of a single photon. Due to interactions between excitons, the emission when the quantum dot contains a single exciton is energetically distinct from that when the quantum dot contains more than one exciton. Therefore, a single exciton can be deterministically created by a laser pulse and the quantum dot becomes a nonclassical light source that emits photons one by one and thus shows photon antibunching. The emission of single photons can be proven by measuring the second order intensity correlation function. The spontaneous emission rate of the emitted photons can be enhanced by integrating the quantum dot in an optical cavity. Additionally, the cavity leads to emission in a well-defined optical mode increasing the efficiency of the photon source.
Rupert Ursin is an Austrian experimental physicist active in the field of quantum entanglement and communications. He founded several companies, e.g. Quantum Technology Laboratories GmbH. and Quantum Industries GmbH and acts currently as CEO in both of theses companies.
Malvin Carl Teich is an American electrical engineer, physicist, and computational neuroscientist which is professor emeritus of electrical engineering at Columbia University and physics at Boston University. He is also a consultant to government, academia, and private industry, where he serves as an advisor in intellectual-property conflicts. He is the coauthor of Fundamentals of Photonics, and of Fractal-Based Point Processes.
