Dynamical multipartite entanglement in a generalized Tavis-Cummings model with XY spin interaction

TL;DR

This paper investigates the dynamical multipartite entanglement in a generalized Tavis-Cummings model with XY spin interaction, revealing how temperature, coupling, and magnetic field influence entanglement dynamics.

Contribution

It introduces a theoretical framework connecting the generalized Tavis-Cummings model to the central spin model and analyzes multipartite entanglement dynamics under various conditions.

Findings

Strong coupling and low temperature are essential for genuine multipartite entanglement.

Magnetic field modulates entanglement period and amplitude.

The model links Tavis-Cummings and central spin models, enhancing understanding of their entanglement properties.

Abstract

Multipartite entanglement is a long-term pursuit in the resource theory, offering a potential resource for quantum metrology. Here, we present the dynamical multipartite entanglement, which is in terms of the quantum Fisher information, of a generalized Tavis-Cummings (TC) model introducing the XY spin interaction. Since our model cannot be solved exactly, we theoretically derive and numerically examine the effective description of our model. By the Holstein-Primakoff transformation, we show the bridge from the generalized TC model to the central spin model. Furthermore, the reduced density matrix of the central spins is presented, which is the prerequisite for calculating multipartite entanglement. We also discuss the effect of the temperature, the coupling constant, and the magnetic field on the dynamical multipartite entanglement in the central spin model, where the central spin is initially unentangled. Strong coupling and low temperature are necessary conditions for a genuine multipartite entanglement in the XY model, and together with the magnetic field, they govern the modulation of both the entanglement period and amplitude. Our results unveil the deep link between the TC model and the central spin model, allowing for a better comprehension of their dynamical multipartite entanglement.