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Fundamental limitations for quantum and nanoscale thermodynamics
Michał Horodecki1, Jonathan Oppenheim
1IFTIA, University of Gdańsk, 80-952 Gdańsk, Poland.
Nature Communications
|June 27, 2013
Summary
We developed a new theory for thermodynamics at the nanoscale and in quantum systems. This reveals fundamental limits on work extraction and shows that thermodynamic transitions are often irreversible at this scale.
Area of Science:
- Thermodynamics
- Statistical Physics
- Quantum Information Theory
Background:
- Classical thermodynamics and statistical physics apply to systems with a large number of particles (thermodynamic limit).
- Research is needed to understand thermodynamic behavior at the nanoscale and when quantum effects are significant.
Purpose of the Study:
- To construct a theory of thermodynamics applicable to the nanoscale and quantum regimes.
- To derive criteria for thermodynamic state transitions in these limits.
- To investigate limitations on work extraction and the efficiency of small heat engines.
Main Methods:
- Application of quantum information theory principles.
- Derivation of general criteria for thermodynamic state transitions.
- Identification of specific free energies for work extraction and its reverse.
Main Results:
- Developed a general theory for thermodynamics at the nanoscale and in quantum systems.
- Derived two distinct free energies quantifying extractable work and its reverse process.
- Identified fundamental limitations on work extraction from non-equilibrium states due to finite size and quantum coherences.
- Demonstrated that thermodynamic transitions are generically irreversible at this scale.
Conclusions:
- Thermodynamic transitions are fundamentally irreversible at the nanoscale and in quantum systems.
- Finite size effects and quantum coherences impose limitations on work extraction.
- Small heat engines exhibit irreversibility during adiabatic stages, impacting their efficiency.
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