Typical behavior of the global entanglement of an open multiqubit system in a non-markovian regime

A.P. MAJTEY; A.R. PLASTINO

INTERNATIONAL JOURNAL OF QUANTUM INFORMATION

WORLD SCIENTIFIC PUBL CO PTE LTD

Lugar: London, UK; Año: 2012 vol. 10 p. 12500631 - 125006316

0219-7499

We investigate the decay of the global entanglement, due to decoherence, of multiqubit systems interacting with a reservoir in a non-Markovian regime. We assume that during the decoherenceprocess each qubit of the system interacts with its own, independent environment. Most previous works on this problem focused on particular initial states or families of initial states amenable ofanalytical treatment. Here we determine numerically the typical, average behavior of the system corresponding to random initial pure states uniformly distributed (in the whole Hilbert space ofn-qubit pure states) according to the Haar measure. We study systems consisting of 3, 4, 5, and 6 qubits. In each case we consider also the entanglement dynamics corresponding to important particular initial states, such as the GHZ states or multiqubit states maximizing the global entanglement, and determine in which cases any of these states is representative of the average behavior associated with general initial states.