Tightening Monogamy and Polygamy Inequalities of Multiqubit Entanglement

Monogamy, Polygamy and other Properties of Entanglement of Purification

For bipartite pure and mixed quantum states, in addition to the quantum mutual information, there is another measure of total correlation, namely, the entanglement of purification. We study the monogamy, polygamy, and additivity properties of the entanglement of purification for pure and mixed states. In this paper, we show that, in contrast to the quantum mutual information which is strictly m...

Monogamy and Polygamy of Entanglement in Multipartite Quantum Systems

One distinct property of quantum entanglement from other classical correlations is that multipartite entanglements cannot be freely shared among the parties: If two parties in a multi-party system share a maximally entangled state, then they cannot share any entanglement with the rest. This is known as monogamy of entanglement (MoE) [1], which is a key ingredient for secure quantum cryptography...

General monogamy relations of quantum entanglement for multiqubit W-class states

Monogamy of Correlations vs. Monogamy of Entanglement

A fruitful way of studying physical theories is via the question whether the possible physical states and different kinds of correlations in each theory can be shared to different parties. Over the past few years it has become clear that both quantum entanglement and non-locality (i.e., correlations that violate Bell-type inequalities) have limited shareability properties and can sometimes even...

Efficient multiqubit entanglement via a spin bus.

We propose an experimentally feasible architecture with controllable long-range couplings built up from local exchange interactions. The scheme consists of a spin bus, with strong, always-on interactions, coupled dynamically to external qubits of the Loss and DiVincenzo type. Long-range correlations are enabled by a spectral gap occurring in a finite-size chain. The bus can also form a hub for ...