Regular Article

Effect of intrinsic decoherence on entanglement of three polar molecules with two-dimensional rotation

¹ Department of Applied Physics, National University of Kaohsiung, Kaohsiung 81148, Taiwan
² Department of Materials Science and Engineering, I-Shou University, Kaohsiung 84001, Taiwan
³ Department of Physics, National Kaohsiung Normal University, Kaohsiung 82444, Taiwan

^a e-mail: yyliao@nuk.edu.tw

Received: 23 July 2018
Received in final form: 10 November 2018
Published online: 7 March 2019

Abstract

The dynamic entanglement of three polar molecules with two-dimensional rotations is investigated under the influence of an electric field and intrinsic decoherence. The parameters of the electric field, such as strength and orientation, are tuned to tailor the rotational properties of the molecules. Due to the two-dimensional rotation and its dipole–dipole interaction, a mechanism of two-molecule transition occurs and leads to specific quantum states in the tripartite system. The components of the states are analyzed by varying the symmetry of the molecular arrangement. We evaluate the negativity to probe the entanglement characteristics of the system. The negativity shows distinct oscillating features for initial GHZ, W, and inverted-W states. These features are suppressed and eventually smoothed in the presence of intrinsic decoherence. We further analyze the contribution of the quantum states to the entanglement. Due to specific selection rules, only two of the states are found to dominate the evolution of the negativity. Among the three cases, the system based on the inverted-W state evolves with the lowest loss of entanglement.