Journal of Physics B Atomic Molecular and Optical Physics

Entanglement dynamics of a pure bipartite system in dissipative environments

Rabia Tahira, Manzoor Ikram, Tasnim Azim, Muhammad Suhail Zubairy

Published Oct 1, 2008• 35 citations

Abstract

We investigate the phenomenon of sudden death of entanglement in a bipartite system subjected to dissipative environments with arbitrary initial pure entangled state between two atoms. We find that in a vacuum reservoir the presence of the state where both atoms are in excited states is a necessary condition for the sudden death of entanglement. Otherwise entanglement remains for an infinite time and decays asymptotically with the decay of individual qubits. For pure 2-qubit entangled states in a thermal environment, we observe that the sudden death of entanglement always happens. The sudden death time of the entangled states is related to the temperature of the reservoir and the initial preparation of the entangled states.

DOI: 10.1088/0953-4075/41/20/205501

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