How an autonomous quantum Maxwell demon can harness correlated information

TL;DR

This paper explores an autonomous quantum Maxwell demon that leverages correlations and quantum coherence to achieve refrigeration and information erasure, surpassing classical thermodynamic limits.

Contribution

It introduces a quantum Maxwell demon model that utilizes correlated quantum information and coherence to enhance thermodynamic performance.

Findings

Correlations enable refrigeration against thermal gradients.

Quantum coherence enhances the demon’s efficiency.

The model demonstrates simultaneous refrigeration and information erasure.

Abstract

We study an autonomous quantum system which exhibits refrigeration under an information-work trade-off like a Maxwell demon. The system becomes correlated as a single "demon" qubit interacts sequentially with memory qubits while in contact with two heat reservoirs of different temperatures. Using strong subadditivity of the von Neumann entropy, we derive a global Clausius inequality to show thermodynamic advantages from access to correlated information. It is demonstrated, in a matrix product density operator formalism, that our demon can simultaneously realize refrigeration against a thermal gradient and erasure of information from its memory, which is impossible without correlations. The phenomenon can be even enhanced by the presence of quantum coherence.