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Reversing the direction of heat flow using quantum correlations
Kaonan Micadei1,2, John P S Peterson3, Alexandre M Souza3
1Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Avenida dos Estados 5001, 09210-580, Santo André, São Paulo, Brazil.
Nature Communications
|June 6, 2019
Summary
Quantum correlations enable heat to flow from cold to hot systems, defying standard thermodynamic principles. This controlled reversal of heat flow highlights the interplay between quantum mechanics, thermodynamics, and information theory.
Area of Science:
- Quantum Thermodynamics
- Statistical Mechanics
- Quantum Information
Background:
- Standard thermodynamics posits heat flows from hot to cold.
- This principle assumes no initial correlations between systems.
- Quantum systems can exhibit correlations not present in classical physics.
Purpose of the Study:
- To experimentally demonstrate the reversal of heat flow.
- To investigate heat flow in quantum correlated systems.
- To explore the interplay of quantum mechanics, thermodynamics, and information theory.
Main Methods:
- Utilized a Nuclear Magnetic Resonance (NMR) setup.
- Prepared two quantum correlated spins-1/2 in local thermal states.
- Quantified energy flow and information-theoretical quantities.
Main Results:
- Observed spontaneous energy flow from a cold to a hot system.
- Demonstrated heat flow reversal in quantum correlated systems.
- Quantified the trade-off between correlations and entropy.
Conclusions:
- Quantum correlations can reverse the direction of heat flow.
- Heat flow is influenced by the interplay of quantum mechanics, thermodynamics, and information.
- Provides a mechanism for controlling heat at the microscale.
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