Entanglement evolution of three-qubit states in a quantum-critical environment

Abstract

We investigate the entanglement dynamics of three-qubit states in a quantum-critical environment, which is an Ising model in a transverse field. By using negativity as entanglement measure, we find that the entanglement evolution depends not only on the system-environment couplings and the size of degrees of freedom of environment but also on the strength of transverse field and the symmetry of quantum states of concern. In particular, for the cases under study, our results imply that the entanglement decay can be enhanced by the quantum phase transition of the environment under weak coupling. Our analysis implies that the entanglement of any three-qubit quantum state will be completely destroyed by the decoherence under certain conditions, that we detail below.

Quantum Discord for a Central Two-Qubit System Coupled to an XY Spin Chain with Energy Current

“…Entanglement is one of the most fascinating features of quantum mechanics and plays a central role in quantum information processing [1][2][3][4]. Much progress concerning quantum entanglement in both theory and experiment has been achieved.…”

Effect of decoherence from a spin environment on the entanglement dynamics of two-qutrit states

“…The extent to which the environment affects quantum entanglement is an interesting problem and much work has been done along the line [18][19][20][21]. Beyond the entanglement dynamics, the researchers have also investigated the state transfer with liquid nuclear magnetic resonance [22], the entanglement creation [23], and the dynamical decoupling [24].…”

Disentanglement of Three-qubit States Coupled to an XY Spin Chain with Multisite Interaction

“…For a two-qubit case under a transverse Ising model, Sun et al discovered that the concurrence decays exponentially with fourth power of time in the vicinity of the critical point of the environment system [13]. The multiqubit case was investigated by Ma et al [14]. For a two-spin coupling to an XY chain with Dzyaloshinsky-Moriya (DM) interaction, Cheng et al found that the DM interaction can enhance slightly the decay of the decoherence factor in the weak coupling region, and in the strong coupling region, the decoherence factor is super-sensitive to the DM interaction [15].…”