# The second law, Maxwell's demon, and work derivable from quantum heat engines.

@article{Kieu2004TheSL, title={The second law, Maxwell's demon, and work derivable from quantum heat engines.}, author={Tien D. Kieu}, journal={Physical review letters}, year={2004}, volume={93 14}, pages={ 140403 } }

With a class of quantum heat engines which consists of two-energy-eigenstate systems undergoing, respectively, quantum adiabatic processes and energy exchanges with heat baths at different stages of a cycle, we are able to clarify some important aspects of the second law of thermodynamics. The quantum heat engines also offer a practical way, as an alternative to Szilard's engine, to physically realize Maxwell's demon. While respecting the second law on the average, they are also capable of…

## 232 Citations

Quantum heat engines, the second law and Maxwell's daemon

- Physics
- 2003

Abstract.We introduce a class of quantum heat engines which consists of
two-energy-eigenstate systems, the simplest of quantum mechanical
systems, undergoing quantum adiabatic processes and energy…

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We introduce a new quantum heat engine, in which the working medium undergoes quantum quasi-adiabatic and non-unitary processes to extract work in the cycle. Two kinds of working medium are…

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The role of Maxwell's demon is discussed and it is found that there is no violation of the second law, even in the existence of such a demon, when the demon is included correctly as part of the working substance of the heat engine.

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By reformulating the first law of thermodynamics in the fashion of quantum-mechanical operators on the parameter manifold, we propose a universal class of quantum heat engines (QHE) using the…

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We study the unitary time evolution of a simple quantum Hamiltonian describing a heat engine coupled to two heat baths. The engine is modeled as a three-level system. Each heat bath consists of a…

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- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
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This work suggests that the measurement postulate of quantum mechanics is intricately connected to the second law of thermodynamics, and challenges the conventional approach of simply quantifying quantum correlations as a thermodynamic work deficit.

Experimental Characterization of a Spin Quantum Heat Engine.

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A quantum heat engine based on a spin-1/2 system and nuclear magnetic resonance techniques is experimentally implemented, able to reach an efficiency for work extraction very close to its thermodynamic limit.

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- Physics
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A new model of a quantum heat engine (QHE) cycle is established, in which the working substance consists of an interacting electrons system. One of our purposes is to test the validity of the second…

The Second Law of Thermodynamics in a Quantum Heat Engine Model

- Physics
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The second law of thermodynamics has been proven by many facts in classical world. Is there any new property of it in quantum world? In this paper, we calculate the change of entropy in T.D. Kieu's…

Efficiency large deviation function of quantum heat engines

- PhysicsNew Journal of Physics
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The efficiency of small thermal machines is typically a fluctuating quantity. We here study the efficiency large deviation properties of two exemplary quantum heat engines, the harmonic oscillator…

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