Optimal control for the preparation of entangled state based on the coupling symmetry in non-Markovian environment

摘要

We investigate the influence of the interaction symmetry between qubits and environment on the preparation and transmission of local entanglement by means of concurrence in the non-Markovian environment. The results indicate that the degree of entanglement between coupling qubits not only depends on the interaction between qubits and the purity of initial quantum states, but also strongly depends on the interaction symmetry between qubits and environment. In the studied model, the decoherence of environment can be completely avoided when the interaction between qubits and environment is symmetrical. The generation of entanglement relies on the difference between the initial quantum states of two qubits. It is easier to generate and maintain entanglement under symmetrical coupling to the environment for two qubits that one is initially in the excited state and the other is in the ground state. Furthermore, the more asymmetrically the qubits interact with environment, the more difficult to prepare efficient entangled states. (C) 2015 Elsevier GmbH. All rights reserved.