Sudden death and sudden birth of entanglement in common structured reservoirs

TL;DR

This paper investigates how entanglement between two qubits evolves in a shared structured reservoir, revealing phenomena like sudden death and birth of entanglement driven by non-Markovian effects.

Contribution

It provides an exact analysis of entanglement dynamics, highlighting the roles of reservoir structure and non-Markovian backaction in entanglement sudden death and birth.

Findings

Entanglement can abruptly disappear or appear depending on initial states.

Non-Markovian reservoir effects cause revivals of entanglement after death.

Periods of disentanglement follow entanglement sudden birth due to reservoir backaction.

Abstract

We study the exact entanglement dynamics of two qubits in a common structured reservoir. We demonstrate that, for certain classes of entangled states, entanglement sudden death occurs, while for certain initially factorized states, entanglement sudden birth takes place. The backaction of the non-Markovian reservoir is responsible for revivals of entanglement after sudden death has occurred, and also for periods of disentanglement following entanglement sudden birth.