Dynamics of quantum correlations and Fisher information of a multipartite system under the Stark effect

Abstract

In this paper, we explore the dynamics of the global quantum discord (GQD) and quantum Fisher information (QFI) of a multipartite two-level stationary and moving atomic system under the Stark shift effect. The system interacts with a thermal field with a different number of average thermal photons. For a fixed Stark parameter value, the GQD magnitudes increase as the system size (N) increases for both static and moving atomic systems. However, in the instance of a stationary atomic system and lower Stark parameter values, the QFI preserves a constant magnitude for different N values. When atomic motion is taken, the quantifier dynamics exhibit periodic oscillations. Additionally, increasing the Stark parameter led to a suppression in the magnitude of both GQD and QFI. With in the sight of intrinsic decoherence (ID), the quantifiers show a damping in their oscillations. Interestingly, the atomic motion assists to mitigate the damping effects caused by ID. Moreover, if the average thermal photons are increased, the magnitude of the GQD and QFI are decreased.

Keywords

• Global quantum discord
• Quantum Fisher information
• Stark shift
• Atomic motion