The entanglement dynamics of interacting qubits embedded in a spin environment with Dzyaloshinsky-Moriya term

TL;DR

This paper studies how entanglement between two qubits evolves within a spin environment influenced by Dzyaloshinsky-Moriya interaction, revealing conditions that enhance or suppress entanglement generation.

Contribution

It introduces a detailed analysis of entanglement dynamics considering Dzyaloshinsky-Moriya interaction and identifies resonance conditions affecting entanglement.

Findings

Entanglement is suppressed at quantum critical points in weak coupling.

Increasing DM interaction or decreasing anisotropy can restore entanglement.

Resonance peaks occur when system-bath coupling matches external magnetic field.

Abstract

We investigate the entanglement dynamics of two interacting qubits in a spin environment, which is described by an XY model with Dzyaloshinsky-Moriya (DM) interaction. The competing effects of environmental noise and interqubit coupling on entanglement generation for various system parameters are studied. We find that the entanglement generation is suppressed remarkably in weak-coupling region at quantum critical point (QCP). However, the suppression of the entanglement generation at QCP can be compensated both by increasing the DM interaction and by decreasing the anisotropy of the spin chain. Beyond the weak-coupling region, there exist resonance peaks of concurrence when the system-bath coupling equals to external magnetic field. We attribute the presence of resonance peaks to the flat band of the self-Hamiltonian. These peaks are highly sensitive to anisotropy parameter and DM interaction.