Entanglement distribution between distant parties is an essential component to most quantum communication protocols. Unfortunately, decoherence effects such as phase noise in optical fibres are known to demolish entanglement. Iterative (multistep) entanglement distillation protocols have long been proposed to overcome decoherence, but their probabilistic nature makes them inefficient since the ...

Quantum entanglement, as one of the most intriguing feature of quantum theory, has been a subject of much studies in recent years, mostly because its nonlocal connotation[1] is regarded as a valuable resource in quantum communication and information processing [2, 3]. One important issue is whether there exists any relation between quantum entanglement and quantum phase transitions [4]. Several...

The field of quantum computing is based on the laws of quantum mechanics, including states superposition and entanglement. Quantum cryptography is amongst the most surprising applications of quantum mechanics in quantum information processing. Remote state preparation allows a known state to a sender to be remotely prepared at a receiver’s location when they prior share entanglement and transmi...

Entanglement, according to Erwin Schrödinger the essence of quantum mechanics, is at the heart of the Einstein-Podolsky-Rosen paradox and of the so called quantum-nonlocality – the fact that a local realistic explanation of quantum mechanics is not possible as quantitatively expressed by violation of Bell’s inequalities. Even as entanglement gains increasing importance in most quantum informati...

Most of the attention given to continuous variable systems for quantum information processing has traditionally been focused on Gaussian states. However, non-Gaussianity is an essential requirement for universal quantum computation and entanglement distillation, and can improve the efficiency of other quantum information tasks. Here we report the experimental observation of genuine non-Gaussian...

Entanglement plays an important role in quantum communication, algorithms, and error correction. Schmidt coefficients are correlated to the eigenvalues of the reduced density matrix. These eigenvalues are used in von Neumann entropy to quantify the amount of the bipartite entanglement. In this paper, we map the Schmidt basis and the associated coefficients to quantum circuits to generate random...

Quantum entanglement is considered to be a central resource of quantum information processing: entanglement is a key ingredient in quantum teleportation [1], and is used to perform conditional two-qubit operations, which are primordial for running a quantum algorithm [2]. There is a large body of literature on the abstract, rather mathematical theory of entanglement [3], of pure as well as of m...

We show how to protect a stream of quantum information from decoherence induced by a noisy quantum communication channel. We exploit preshared entanglement and a convolutional coding structure to develop a theory of entanglementassisted quantum convolutional coding. Our construction produces a Calderbank-Shor-Steane (CSS) entanglement-assisted quantum convolutional code from two arbitrary class...

Three inter-related topics are discussed here. One, the Lindblad dynamics of quantum dissipative systems; two, quantum entanglement in composite systems and its quantification based on the Tsallis entropy; and three, robustness of entanglement under dissipation. After a brief review of the Lindblad theory of quantum dissipative systems and the idea of quantum entanglement in composite quantum s...

We review the criteria for separability and quantum entanglement, both in a bipartite as well as a multipartite setting. We discuss Bell inequalities, entanglement witnesses, entropic inequalities, bound entanglement and several features of multipartite entanglement. We indicate how these criteria bear on the experimental detection of quantum entanglement.