Eur. Phys. J. D 56, 255-264 (2010)
https://doi.org/10.1140/epjd/e2009-00247-9

Decay of entanglement in coupled, driven systems with bipartite decoherence

Low Temperature Laboratory, Helsinki University of Technology, P.O. Box 5100, 02015 TKK, Finland

Corresponding author: paraoanu@cc.hut.fi

Received: 3 June 2009
Revised: 23 July 2009
Published online: 19 September 2009

Abstract

We analyze a system of two qubits embedded in two different environments. The qubits are coupled to each other and driven on-resonance by two external classical sources. In the secular limit, we obtain exact analytical results for the evolution of the system for several classes of two-qubit mixed initial states. For Werner states we show that the decay of entanglement does not depend on coupling. For other initial states with “X"-type density matrices we find that the sudden death time displays a rich dependence on the coupling energy and state parameters due to the existence of processes of delayed sudden birth of entanglement.