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arXiv · 2405.13412

Sudden change of genuine multipartite entanglement in non-Markovian dynamics

Mazhar Ali
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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.

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Mazhar Ali. 2024-05-22. Sudden change of genuine multipartite entanglement in non-Markovian dynamics. https://doi.org/10.1139/cjp-2023-0173

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