Next Article in Journal
PCA-Based Matrix CFAR Detection for Radar Target
Next Article in Special Issue
Quantum Work Statistics with Initial Coherence
Previous Article in Journal
Prognosis of Diabetic Peripheral Neuropathy via Decomposed Digital Volume Pulse from the Fingertip
Previous Article in Special Issue
Thermodynamics of a Phase-Driven Proximity Josephson Junction
Article

Otto Engine: Classical and Quantum Approach

1
Departamento de Física, Universidad Técnica Federico Santa María, Casilla 110-V, Valparaíso 2390123, Chile
2
Centro para el Desarrollo de la Nanociencia y la Nanotecnología, Santiago 8320000, Chile
*
Author to whom correspondence should be addressed.
Entropy 2020, 22(7), 755; https://doi.org/10.3390/e22070755
Received: 31 May 2020 / Revised: 25 June 2020 / Accepted: 29 June 2020 / Published: 9 July 2020
(This article belongs to the Special Issue Thermodynamics of Quantum Information)
In this paper, we analyze the total work extracted and the efficiency of the magnetic Otto cycle in its classic and quantum versions. As a general result, we found that the work and efficiency of the classical engine is always greater than or equal to its quantum counterpart, independent of the working substance. In the classical case, this is due to the fact that the working substance is always in thermodynamic equilibrium at each point of the cycle, maximizing the energy extracted in the adiabatic paths. We apply this analysis to the case of a two-level system, finding that the work and efficiency in both the Otto’s quantum and classical cycles are identical, regardless of the working substance, and we obtain similar results for a multilevel system where a linear relationship between the spectrum of energies of the working substance and the external magnetic field is fulfilled. Finally, we show an example of a three-level system in which we compare two zones in the entropy diagram as a function of temperature and magnetic field to find which is the most efficient region when performing a thermodynamic cycle. This work provides a practical way to look for temperature and magnetic field zones in the entropy diagram that can maximize the power extracted from an Otto magnetic engine. View Full-Text
Keywords: thermodynamics; heat engines; quantum thermodynamics thermodynamics; heat engines; quantum thermodynamics
Show Figures

Figure 1

MDPI and ACS Style

Peña, F.J.; Negrete, O.; Cortés, N.; Vargas, P. Otto Engine: Classical and Quantum Approach. Entropy 2020, 22, 755. https://doi.org/10.3390/e22070755

AMA Style

Peña FJ, Negrete O, Cortés N, Vargas P. Otto Engine: Classical and Quantum Approach. Entropy. 2020; 22(7):755. https://doi.org/10.3390/e22070755

Chicago/Turabian Style

Peña, Francisco J., Oscar Negrete, Natalia Cortés, and Patricio Vargas. 2020. "Otto Engine: Classical and Quantum Approach" Entropy 22, no. 7: 755. https://doi.org/10.3390/e22070755

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop