Preparation of quantum correlations assisted by a steering Maxwell demon

Area of Science:

• Quantum thermodynamics
• Quantum information theory
• Quantum correlations

Background:

• Maxwell's demon can reduce system entropy via environmental measurements.
• Nonsignaling theorem limits the demon's influence on the average system state.
• Quantum correlations, including entanglement and steering, are crucial in quantum information processing.

Purpose of the Study:

• Investigate the preparation of quantum correlations (mutual information, entanglement, Bell-nonlocality) using a Maxwell demon.
• Explore the relationship between quantum steering and thermodynamic correlations.
• Determine optimal demon measurement strategies for maximizing quantum correlations.

Main Methods:

• Studied quantum correlation preparation assisted by a demon obtaining environmental information.
• Analyzed demon's ability to influence post-measurement states via measurement choice.
• Derived optimal protocols for creating maximal correlations and established bounds using classical correlations.

Main Results:

• Demon's measurement choice influences post-measured system states, linking steering to thermodynamics.
• Maximal quantum correlations (mutual information, entanglement, Bell-nonlocality) are achieved at the steerable boundary of system-environment states.
• Upper bounds on prepared correlations were derived using classical environment-system correlations.

Conclusions:

• Maxwell demon can actively prepare quantum correlations, extending beyond simple entropy reduction.
• The study establishes a direct link between quantum steering, entanglement, and thermodynamic principles.
• Optimal demon strategies and classical bounds provide insights into the fundamental limits of correlation generation.