Entanglement of Bell diagonal mixed states

Chengjie Zhang, Yong-Sheng Zhang, Guang‐Can Guo

Song Wei

We propose a protocol for teleportation of arbitrary mixture of diagonal Bell states, it is shown that the channel can be constructed with either pure maximally entangled states or mixed bound entangled states. We also present protocols to realize the controlled teleportation of mixture of diagonal Bell states via multi-particle mixed states. Our results show that bound entangled states are also important and useful resources in quantum communication tasks.

Anna Chiara Lai, Marco Pedicini, Silvia Rognone

Li-Xiang Cen, Nanjian Wu, Fuhua Yang +1 more

The optimal entanglement manipulation for a single copy of mixed states of two qubits is to transform it to a Bell diagonal state. In this paper we derive an explicit form of the local operation that can realize such a transformation. The result obtained is universal for arbitrary entangled two-qubit states and it discloses that the corresponding local filter is not unique for density matrices with rank $n=2$ and can be exclusively determined for that with $n=3$ and 4. As illustrations, a four-parameter family of mixed states are explored, the local filter as well as the transformation probability are given explicitly, which verify the validity of the general result.

G. Fano, S. M. Blinder

Varsha Sambhaje, Suprabhat Sinha, Anju Chaurasia

Bell states are special sets of entangled states that serve as a foundation for the corresponding Hilbert space. Being the maximally entangled states, they have significant importance in the field of quantum information theory. Among the mixed two-qubit state space, a highly intriguing limited class of states is the Bell diagonal states. Despite their inherent simplicity, Bell diagonal states exhibits a diverse range of correlations. In this paper, we explore the behaviour of Bell diagonal states under different quantum channels to pursue the geometrical illustration of quantum correlations leading to the entanglement. We propose the convex combination of distinct Bell states to prepare the Bell diagonal states. The whole class of Bell diagonal states is generated and entanglement is simulated throughout each parameter space and compared to the theory.