Decay of two-qubit correlations in the squeezed Bloch channel

Abstract

The decay of correlations between two qubits under the influence of a squeezed thermal reservoir is investigated by means of the quantum master equation in the Born–Markov approximation. To find the effect of the reservoir squeezing on the two-qubit correlations, concurrence, quantum discord, classical correlation and total correlation are calculated for the X-states. It is found that, except for quantum discord, the reservoir squeezing always suppresses the decay of the correlations during the time evolution. On the other hand, for quantum discord, the reservoir squeezing enhances the decay in the initial and intermediate time regions while it reduces the decay in the long time region.

Keywords:

• entanglement
• quantum discord
• qubit
• reservoir
• squeezing
• quantum optics (inc. quantum information)