Dynamics of quantum discord in a two-qubit system under classical noise

F. Kuate Fodouop, Tsamouo Tsokeng Arthur, Pernel Nguenang +2 more

Xiong Yang, Jia-hua Xiao

J. Taghipour, B. Mojaveri, Alireza Dehghani

You-neng Guo, Mao-Fa Fang, Bai-Yuan Yang +2 more

You-neng Guo, Mao-Fa Fang, Xiang Liu +1 more

We study the quantum discord dynamics of two noninteracting qubits that are, respectively, subject to classical noise. The results show that the dynamics of quantum discord are dependent on both the coupling between the qubits and classical noise, and the average switching rate of the classical noise. In the weak-coupling Markovian region, quantum discord exhibits exponent decay without revival, and can be well protected by increasing the average classical noise switching rate. While in the strong-coupling non-Markovian region, quantum discord reveals slowly decayed oscillations with quick revival by decreasing the average switching rate of the classical noise. Thus, our results provide a new method of protecting quantum discord in a two-qubit system by controlling the coupling between the qubits and classical noise, and the average switching rate of the classical noise.

Ying-Jie Zhang, Xu‐Bo Zou, Yun‐Jie Xia +1 more

We analyze the roles of initial correlations between the two-qubit system and a dissipative cavity on quantum discord dynamics of two qubits. Considering two initial system-cavity states, we show that the initial system-cavity correlations not only can initially increase the two-qubit quantum discord but also would lead to a larger long-time quantum discord asymptotic value. Moreover, quantum discord due to initial correlations is more robust than the case of the initial factorized state. Finally, we show the initial correlations' importance for dynamics behaviors of mutual information and classical correlation.