Environment and initial state engineered dynamics of quantum and classical correlations

Exact analytical solution of Quantum Discord for Generalized Werner-Like Non-X states

“…3 The range of variation of the mixing parameter p is now − 1 3 ≤ p ≤ 1, which guarantees the positivity of the GWLs. The parameter p, considered in the expression (6), is understood as a probability when the range of variation is 0 ≤ p ≤ 1. In this case the GWLs represents a convex sum of the density matrix of the GBps |ψ and non-coherent density matrix of an unpolarized state (white noise), with probabilities p and 1 − p, respectively.…”

“…) are used to built the projector Pψ in the expression (6). One difference between the states (4) and ( 6) is that the Ws are X states while that the GWLs are not-X states in general, unless z 1 = z 4 = 0 or z 2 = z 3 = 0; like the WPs, QWs and BWLs.…”

“…To determine the quantum information of each partition of the system H 2 ⊗ H 2 contained in GWLs, given the equation (6), is sufficient to take their partial traces, so that we have to…”

“…On the other hand, the density matrix for the GWLs built with the pure states given in the equations (43a), (43b) and (43c) are non-X states, while the pure state given in the equation ( 43d) is a X-state. Thus, using the expression (6) we obtained that the density matrices for the GWLs built with the aforementioned pure states have the following form…”

“…Entanglement is an inevitable feature of not only quantum theory but also any non-classical theory [2], and this is necessary for emergent classicality in all physical theories. The study of quantum correlation quantifiers other than entanglement, such as the Quantum Discord (QD), has a crucial importance for the full development of new quantum technologies because it is more robust than entanglement against the effects of decoherence [3][4][5][6], and can be among others a resource in quantum computation [7][8][9], quantum non-locality [10], quantum key distribution [11], remote state preparation [12], quantum cryptography [13] and quantum coherence [14].…”