Classification of different forms of quantum entanglement is an active area of research, central to development of effective quantum computers, and similar to classification of error-correction codes, where code duality is broadened to equivalence under all ’local’ unitary transforms. We explore links between entanglement, coding theory, and sequence design, by examining multi-spectra of quantu...

Prior entanglement between sender and receiver, which exactly doubles the classical capacity of a noiseless quantum channel, can increase the classical capacity of some noisy quantum channels by an arbitrarily large constant factor depending on the channel, relative to the best known classical capacity achievable without entanglement. The enhancement factor is greatest for very noisy channels, ...

Quantum information and computation, based on quantum correlations of quantum systems, is one of the promising new fields of physics and information science. Entanglement is the key resource of quantum information processing. However, it is shown recently that quantum entanglement is not the only kind of quantum correlations useful for quantum information processing. Quantum systems without any...

In this paper, we review the investigation for the light-matter interaction between surface plasmon field in metal nanoparticle (MNP) and the excitons in semiconductor quantum dots (SQDs) in hybrid SQD-MNP system under the full quantum description. The exciton-plasmon interaction gives rise to the modified decay rate and the exciton energy shift which are related to the exciton energy by using ...

In this paper, von Neumann entropy is used to study three kinds of bipartite qutrit model, which represent SU(3) strongly correlated model, three-level Lipkin-Meshkov-Glick model, and spin-1 model. The relation between the ground-state entanglement and the quantum phase transition in those models is exhibited and the connection between the entanglement extremes and the symmetries is also discus...

In alternative disentanglement based quantum cryptosystem, classical channel cannot be used when the system is protected by no-cloning principle. But for the similar security criterion , it is discussed that classical channel can be used in alternative entanglement based quantum cryptosystem. A prototype of conventional entanglement based cryptosystem is recovered from alternative entanglement ...

In this Letter we discuss the entanglement near a quantum phase transition by analyzing the properties of the concurrence for a class of exactly solvable models in one dimension. We find that entanglement can be classified in the framework of scaling theory. Further, we reveal a profound difference between classical correlations and the non-local quantum correlation, entanglement: the correlati...

A strong entanglement monotone, which never increases under local operations and classical communications (LOCC), restricts quantum entanglement manipulation more strongly than the usual monotone since the usual one does not increase on average under LOCC. We propose new strong monotones in mixed-state entanglement manipulation under LOCC. These are related to the decomposability and 1-positivi...

Entanglement contains one of the most interesting features of quantum mechanics, often named quantum non-locality[1, 2]. This means entangled states are not separable regardless of the spatial separation of their components. Measurement results on one particle of a two-particle entangled state define the state of the other particle instantaneously with neither particle enjoying its own well-def...

Squeezing of quantum fluctuations by means of entanglement is a well-recognized goal in the field of quantum information science and precision measurements. In particular, squeezing the fluctuations via entanglement between 2-level atoms can improve the precision of sensing, clocks, metrology, and spectroscopy. Here, we demonstrate 3.4 dB of metrologically relevant squeezing and entanglement fo...