Disentanglement of two qubits coupled to an XY spin chain: Role of quantum phase transition

TL;DR

This paper investigates how quantum phase transitions in an XY spin chain environment significantly accelerate the disentanglement of two coupled qubits, revealing scaling behaviors and enhancing understanding of decoherence near critical points.

Contribution

It provides analytical and numerical insights into the impact of quantum phase transitions on qubit disentanglement dynamics in spin-chain environments.

Findings

Disentanglement is greatly enhanced near the QPT.

Scaling behavior in disentanglement dynamics is revealed.

QPT influences decoherence in qubit systems.

Abstract

We study the disentanglement of two spin qubits which interact with a general XY spin-chain environment. The dynamical process of the disentanglement is numerically and analytically investigated in the vicinity of quantum phase transition (QPT) of the spin chain in both weak and strong coupling cases. We find that the disentanglement of the two qubits is in general enhanced greatly when the environmental spin chain is exposed to QPT. We give a detailed analysis to facilitate the understanding of the QPT-enhanced decaying behavior of the disentanglement factor. Furthermore, the scaling behavior in the disentanglement dynamics is also revealed and analyzed.