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Gate-tunable charge carrier electrocaloric effect in trilayer graphene
Natalia Cortés1, Oscar Negrete2,3, Francisco J Peña2
1Departamento de Física, Universidad Técnica Federico Santa María, Casilla 110V, Valparaíso, Chile. natalia.cortesm@usm.cl.
Scientific Reports
|November 10, 2021
Summary
The electrocaloric effect in trilayer graphene (TLG) can be controlled by electric fields, offering tunable cooling or heating. Stacking arrangement significantly influences this thermal response in van der Waals materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- The electrocaloric (EC) effect describes temperature and entropy changes in materials due to electric fields.
- Graphene-based materials are explored for novel electronic and thermal properties.
Purpose of the Study:
- Investigate the electrocaloric effect in trilayer graphene (TLG) structures.
- Analyze the influence of stacking arrangement and gate fields on the EC response.
- Propose a novel charge carrier electrocaloric effect in quantum layered systems.
Main Methods:
- Tight-binding calculations combined with Fermi statistics.
- Analysis of electronic density of states (DOS) at the Fermi level.
- Simulation of external gate field effects on TLG.
Main Results:
- EC effect in TLG is sensitive to stacking: AAA shows inverse (cooling), ABC shows direct (heating) above room temperature.
- Bernal-ABA stacked TLG exhibits both direct and inverse EC responses.
- Gate-dependent electronic transitions drive the EC effect in ABA-TLG.
Conclusions:
- Trilayer graphene offers a versatile platform for controlling thermal responses via the electrocaloric effect.
- Stacking arrangement is crucial for tuning the EC effect in layered quantum systems.
- The proposed charge carrier EC effect opens avenues for novel nanodevices.
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