Sudden change of genuine multipartite entanglement in non-Markovian dynamics

TL;DR

This paper explores how non-Markovian dynamics influence the sudden changes and revival phenomena of genuine multipartite entanglement in cavity-reservoir systems, revealing prolonged entanglement and recurrent sudden change behavior.

Contribution

It demonstrates the impact of non-Markovian effects on entanglement dynamics, including prolongation, delayed birth, and recurrent sudden changes in genuine multipartite entanglement.

Findings

Non-Markovianity prolongs entanglement life and causes collapse/revival.

Entanglement sudden birth in reservoirs is delayed with oscillations.

Genuine entanglement can develop, reach a maximum, freeze, then decay, with potential recurrence.

Abstract

We investigate entanglement dynamics of bipartite as well multipartite systems beyond Markov approximation. We study two pairs of cavity-reservoir systems, modeled as four qubits and track the change of entanglement among cavity-cavity qubits, reservoir-reservoir qubits, and also for genuine entanglement of all four qubits. For cavity-cavity qubits, we find that non-Markovianity prolongs the life of entanglement besides collapse/revival phenomenon. For reservoir-reservoir qubits, entanglement sudden birth is delayed accordingly along with oscillations. For all four qubits, with a specific initial state, we find that genuine entanglement develops gradually, reaches to a maximum constant value and then freezes at this value for some time before decaying. This sudden change in dynamics of genuine entanglement occurs for a time window where neither cavities nor reservoirs are entangled. In contrast to Markov process, sudden change phenomenon may be recurrent in non-Markovian regime.