https://doi.org/10.1140/epjd/e2013-40536-0
Regular Article
Quantum Stirling heat engine and refrigerator with single and coupled spin systems
1 School of Physics and Electronic
Technology, Liaoning Normal University, Dalian
116029, P.R.
China
2 School of Physics and Optoelectronic
Technology, Dalian University of Technology, Dalian
116024, P.R.
China
3 College of Mathematics and Physics,
Bohai University, Jinzhou
121013, P.R.
China
a e-mail: ghost820521@163.com
b
e-mail: yixx@dlut.edu.cn
Received:
29
August
2013
Received in final form:
20
November
2013
Published online:
20
February
2014
We study the reversible quantum Stirling cycle with a single spin or two coupled spins as the working substance. With the single spin as the working substance, we find that under certain conditions the reversed cycle of a heat engine is NOT a refrigerator, this feature holds true for a Stirling heat engine with an ion trapped in a shallow potential as its working substance. The efficiency of quantum Stirling heat engine can be higher than the efficiency of the Carnot engine, but the performance coefficient of the quantum Stirling refrigerator is always lower than its classical counterpart. With two coupled spins as the working substance, we find that a heat engine can turn to a refrigerator due to the increasing of the coupling constant, this can be explained by the properties of the isothermal line in the magnetic field-entropy plane.
Key words: Atomic Physics
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag 2014