About the Definition of the Local Equilibrium Lattice Temperature in Suspended Monolayer Graphene
The definition of temperature in non-equilibrium situations is among the most controversial questions in thermodynamics and statistical physics. In this paper, by considering two numerical experiments simulating charge and phonon transport in graphene, two different definitions of local lattice temp...
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| Format: | Article |
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MDPI AG
2021-07-01
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| Series: | Entropy |
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| Online Access: | https://www.mdpi.com/1099-4300/23/7/873 |
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| author | Marco Coco Giovanni Mascali Vittorio Romano |
| author_facet | Marco Coco Giovanni Mascali Vittorio Romano |
| author_sort | Marco Coco |
| collection | DOAJ |
| description | The definition of temperature in non-equilibrium situations is among the most controversial questions in thermodynamics and statistical physics. In this paper, by considering two numerical experiments simulating charge and phonon transport in graphene, two different definitions of local lattice temperature are investigated: one based on the properties of the phonon–phonon collision operator, and the other based on energy Lagrange multipliers. The results indicate that the first one can be interpreted as a measure of how fast the system is trying to approach the local equilibrium, while the second one as the local equilibrium lattice temperature. We also provide the explicit expression of the macroscopic entropy density for the system of phonons, by which we theoretically explain the approach of the system toward equilibrium and characterize the nature of the equilibria, in the spatially homogeneous case. |
| first_indexed | 2024-03-10T09:40:44Z |
| format | Article |
| id | doaj.art-fba56a6c1ffe4c238a09f9f75fa6ba25 |
| institution | Directory Open Access Journal |
| issn | 1099-4300 |
| language | English |
| last_indexed | 2024-03-10T09:40:44Z |
| publishDate | 2021-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Entropy |
| spelling | doaj.art-fba56a6c1ffe4c238a09f9f75fa6ba252023-11-22T03:45:08ZengMDPI AGEntropy1099-43002021-07-0123787310.3390/e23070873About the Definition of the Local Equilibrium Lattice Temperature in Suspended Monolayer GrapheneMarco Coco0Giovanni Mascali1Vittorio Romano2Department of Industrial Engineering and Mathematical Sciences, Università Politecnica delle Marche, Via Brecce Bianche, 12, 60131 Ancona, ItalyDepartment of Mathematics and Computer Science, Università degli Studi della Calabria and INFN-Gruppo c. Cosenza, 87036 Cosenza, ItalyDepartment of Mathematics and Computer Science, Università degli Studi di Catania, Viale Andrea Doria 6, 95125 Catania, ItalyThe definition of temperature in non-equilibrium situations is among the most controversial questions in thermodynamics and statistical physics. In this paper, by considering two numerical experiments simulating charge and phonon transport in graphene, two different definitions of local lattice temperature are investigated: one based on the properties of the phonon–phonon collision operator, and the other based on energy Lagrange multipliers. The results indicate that the first one can be interpreted as a measure of how fast the system is trying to approach the local equilibrium, while the second one as the local equilibrium lattice temperature. We also provide the explicit expression of the macroscopic entropy density for the system of phonons, by which we theoretically explain the approach of the system toward equilibrium and characterize the nature of the equilibria, in the spatially homogeneous case.https://www.mdpi.com/1099-4300/23/7/873local equilibrium temperatureelectron–phonon transportgraphenemacroscopic modelsmaximum entropy principle |
| spellingShingle | Marco Coco Giovanni Mascali Vittorio Romano About the Definition of the Local Equilibrium Lattice Temperature in Suspended Monolayer Graphene Entropy local equilibrium temperature electron–phonon transport graphene macroscopic models maximum entropy principle |
| title | About the Definition of the Local Equilibrium Lattice Temperature in Suspended Monolayer Graphene |
| title_full | About the Definition of the Local Equilibrium Lattice Temperature in Suspended Monolayer Graphene |
| title_fullStr | About the Definition of the Local Equilibrium Lattice Temperature in Suspended Monolayer Graphene |
| title_full_unstemmed | About the Definition of the Local Equilibrium Lattice Temperature in Suspended Monolayer Graphene |
| title_short | About the Definition of the Local Equilibrium Lattice Temperature in Suspended Monolayer Graphene |
| title_sort | about the definition of the local equilibrium lattice temperature in suspended monolayer graphene |
| topic | local equilibrium temperature electron–phonon transport graphene macroscopic models maximum entropy principle |
| url | https://www.mdpi.com/1099-4300/23/7/873 |
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