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Updated: Nov 27, 2025
05:20
Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
18.9K
Ballistic-Diffusive Model for Heat Transport in Superlattices and the Minimum Effective Heat Conductivity
Federico Vázquez1, Péter Ván2,3,4, Róbert Kovács2,3,4
1Department of Physics, UAEM, Science Research Center, Av. Universidad 1001, 62209 Cuernavaca, Mexico.
Entropy (Basel, Switzerland)
|December 8, 2020
Summary
Semiconductor superlattices exhibit minimum thermal conductivity at the nanoscale. A new thermodynamic theory explains this phenomenon by separating heat fluxes, crucial for thermoelectric devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Semiconductor superlattices are of interest due to their low thermal conductivities.
- Their properties are suitable for thermoelectric energy generation and nanoscale heat control.
- Experimental data show a minimum in effective thermal conductivity for nanoperiod superlattices.
Purpose of the Study:
- To advance a thermodynamic theory for heat transport in nanometric 1D multilayer systems.
- To explain the observed minimum in effective thermal conductivity of superlattices.
Main Methods:
- Separation of ballistic and diffusive heat fluxes.
- Application of Guyer-Krumhansl constitutive equations.
- Derivation of dispersion relations from heat transport equations.
Main Results:
- An effective heat conductivity for superlattices was derived.
- The derived theory explains the minimum in effective thermal conductivity at specific periods.
Conclusions:
- The thermodynamic theory provides a framework for understanding heat transport in nanometric multilayer systems.
- The findings support the design of advanced thermoelectric materials and nanoscale thermal management devices.
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