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Large Scale Energy Efficient Sensor Network Routing Using a Quantum Processor Unit

Large Scale Energy Efficient Sensor Network Routing Using a Quantum Processor Unit

Published on: September 8, 2023

Quantum Maxwell's demon in thermodynamic cycles.

H Dong¹, D Z Xu, C Y Cai

¹Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing, China.

Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics

|July 30, 2011

Summary

This summary is machine-generated.

Maxwell's demon (MD) enhances work output in quantum thermodynamic cycles. Quantum coherence or lower temperatures in the demon boost the system's ability to perform work, validating thermodynamics.

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Area of Science:

Thermodynamics
Quantum Mechanics
Statistical Mechanics

Background:

Maxwell's demon (MD) is a thought experiment exploring the limits of the second law of thermodynamics.
Classical interpretations often overlook quantum effects and finite-size impacts on thermodynamic cycles.

Purpose of the Study:

To investigate the physical mechanism of Maxwell's demon in a quantum thermodynamic cycle.
To explore how quantum coherence and temperature differences affect the demon's work enhancement capabilities.
To analyze the finite-size effects and validity of the second law in quantum Szilard heat engines.

Main Methods:

Modeling the Maxwell's demon as a two-level system (TLS) interacting with a single molecule in a potential well.
Describing the thermodynamic cycle processes using quantum mechanics.
Evaluating the efficiency of a quantum Szilard heat engine (SHE) under various conditions.

Main Results:

A Maxwell's demon with quantum coherence or at a lower temperature than the heat bath enhances the total work output.
The demon's key role is driving the system out of equilibrium, creating effective temperature differences.
Finite-size effects deviate from classical expectations, particularly for the quantum Szilard heat engine.

Conclusions:

Quantum coherence and tailored temperature baths are crucial for enhancing work extraction via Maxwell's demon.
The study confirms the second law of thermodynamics even in quantum regimes with finite-size effects.
The quantum model provides a deeper understanding of information-driven thermodynamics beyond classical limits.