Postponing Distillability Sudden Death in a Correlated Dephasing Channel

Area of Science:

• Quantum Information Science
• Quantum Dynamics
• Entanglement Theory

Background:

• Quantum channels describe the evolution of quantum states.
• Entanglement is a key quantum resource, but it can be fragile.
• Distillability sudden death (DSD) is a phenomenon where entanglement is abruptly lost.

Purpose of the Study:

• To investigate the impact of correlated quantum channels on entanglement dynamics.
• To explore the potential of partial and full correlations to mitigate DSD.
• To analyze the behavior of entanglement negativity in such systems.

Main Methods:

• Studied a two-qutrit system interacting with a correlated quantum channel.
• Analyzed the evolution of quantum states under channel actions.
• Quantified entanglement using measures like negativity.

Main Results:

• Partial correlations in the channel can postpone DSD.
• A broader range of time cutoffs for positive partial transpose states is observed.
• In fully correlated channels, entanglement negativity revives, and DSD is eliminated.

Conclusions:

• Correlated quantum channels offer a mechanism to preserve entanglement.
• The degree of correlation is crucial for overcoming entanglement sudden death.
• This research opens avenues for robust quantum information processing.