Dissipative dynamics of quantum discord under quantum chaotic environment

TL;DR

This paper studies how quantum discord evolves over time in a system where two initially entangled qubits interact with a quantum chaotic environment modeled by a quantum kicked top, revealing the relationship between discord decay and fidelity decay.

Contribution

It introduces a model combining quantum discord dynamics with a quantum kicked top environment and compares it to multi-mode oscillator environments, highlighting the role of fidelity decay.

Findings

Long-term quantum discord behavior correlates with fidelity decay.

Short-term dynamics depend on the phase of fidelity decay amplitude.

Quantum discord decay differs from entanglement decay in the studied system.

Abstract

We investigate the dissipative dynamics of quantum discord in a decoherence model with two initially entangled qubits in addition to a quantum kicked top. The two qubits are uncoupled during the period of our study and one of them interacts with the quantum kicked top. We find that the long time behavior of quantum discord could be well described by the fidelity decay of the quantum kicked top; for short time behavior, however, the phase of the amplitude of the fidelity decay is necessary to provide more specific information about the system. We have made comparison between the quantum kicked top and multi-mode oscillator system in describing environment, and also compared the dynamics of the entanglement with that of quantum discord.