Tripartite separability of four-qubit W and Dicke mixed state in noise environment
College of Information and Electronic Engineering (Sussex Artificial Intelligence Institute), Zhejiang Gongshang University, 310018, Hangzhou, China
2 School of Information & Electrical Engineering, Zhejiang University City College, 310015, Hangzhou, China
Accepted: 3 July 2021
Published online: 10 July 2021
Quantum entanglement is one of the most important resources in quantum information. A certain degree of white noise will make the entangled state separable, so finding the minimal white noise tolerance of a specific state is important. Based on a detailed study of the tripartite separability of a four-qubit W state mixed with a Dicke state and white noise, we obtain the necessary and (or) sufficient conditions either numerically or analytically. In particular, we give the analytical formula at W state side, our results show that the sufficient condition of tripartite separability agrees with the necessary condition well.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2021