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Irreversible work and inner friction in quantum thermodynamic processes.
F Plastina1, A Alecce2, T J G Apollaro3
1Dip. Fisica, Università della Calabria, 87036 Arcavacata di Rende (CS), Italy and INFN-Gruppo collegato di Cosenza, Cosenza, Italy.
Physical Review Letters
|January 24, 2015
Summary
This study explores thermodynamics in non-equilibrium quantum systems, introducing concepts of irreversible work and inner friction. These are linked to heat exchange and relative entropy, with a fluctuation relation for inner friction entropy production.
Area of Science:
- Thermodynamics
- Quantum Mechanics
- Statistical Physics
Background:
- Understanding non-equilibrium thermodynamics in quantum systems is crucial.
- Unitary processes in closed quantum systems present unique thermodynamic challenges.
Purpose of the Study:
- To investigate the thermodynamics of closed quantum systems driven out of equilibrium.
- To compare actual work done with ideal transformations (adiabatic, isothermal).
- To introduce and analyze irreversible work and inner friction.
Main Methods:
- Analysis of unitary processes in driven quantum systems.
- Comparison of actual work with work from adiabatic and isothermal transformations.
- Derivation of fluctuation relations for entropy production.
Main Results:
- Introduced irreversible work and inner friction by comparing actual work to ideal processes.
- Demonstrated that irreversible work and inner friction are equivalent, linked to heat exchange and relative entropy.
- Established a fluctuation relation for entropy production associated with inner friction.
Conclusions:
- Irreversible work and inner friction are fundamental concepts in non-equilibrium quantum thermodynamics.
- These quantities can be unified and expressed using relative entropies.
- Inner friction can be quantified via its entropy production and cumulants through fluctuation relations.
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