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Reversing Heat Flow by Coherence in a Multipartite Quantum System
Keyi Huang1, Qi Zhang2, Xiangjing Liu3
1Southern University of Science and Technology, Department of Physics, State Key Laboratory of Quantum Functional Materials, and Guangdong Basic Research Center of Excellence for Quantum Science, Shenzhen 518055, China.
Physical Review Letters
|February 22, 2026
Summary
Quantum coherence in multipartite spin systems can reverse heat flow, challenging classical thermodynamics. Local quantum properties allow precise control over energy transfer direction and magnitude.
Area of Science:
- Quantum Thermodynamics
- Quantum Information Science
- Condensed Matter Physics
Background:
- The second law of thermodynamics traditionally dictates spontaneous heat flow from hot to cold.
- Recent studies show quantum correlations can reverse this flow, challenging classical expectations.
- Internal quantum states, not just environmental correlations, are explored for heat flow control.
Purpose of the Study:
- To experimentally demonstrate heat flow reversal using internal quantum coherence.
- To investigate the role of coherence in multipartite spin systems for energy transfer.
- To establish control over heat flow direction and magnitude via local quantum properties.
Main Methods:
- Utilizing a multipartite spin system with internal quantum coherence.
- Employing the collision model with cascade interaction for simulation.
- Analyzing the impact of coherence strength and phase on energy transfer.
Main Results:
- Internal quantum coherence was shown to reverse heat flow without environmental correlations.
- The strength and phase of coherence were found to dictate energy transfer direction and magnitude.
- Precise control over heat flow was achieved using only local quantum properties.
Conclusions:
- Internal quantum coherence is a viable mechanism for reversing heat flow.
- Quantum properties offer novel methods for manipulating thermodynamic processes.
- This research opens avenues for controlling energy transfer at the quantum level.
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