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Updated: Oct 9, 2025
05:20
Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
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Thermoelectric Transport in a Three-Dimensional HgTe Topological Insulator
Gennady M Gusev1, Ze D Kvon2,3, Alexander D Levin1
1Instituto de Física, Universidade de São Paulo, São Paulo 135960-170, Brazil.
Nanomaterials (Basel, Switzerland)
|December 24, 2021
Summary
Thermoelectric properties of strained mercury telluride (HgTe) films were experimentally investigated. Phonon drag primarily contributes to thermopower, with scattering effects modifying the Seebeck coefficient in specific electronic regimes.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Strained mercury telluride (HgTe) films are recognized as three-dimensional topological insulators (3D TIs).
- Understanding thermoelectric properties is crucial for potential device applications.
Purpose of the Study:
- To experimentally investigate the thermoelectric response of strained HgTe films.
- To elucidate the dominant contributions to thermopower and the Seebeck coefficient.
Main Methods:
- Experimental measurement of thermoelectric response in 80 nm-thick strained HgTe films.
- Comparison of experimental data with theoretical models.
Main Results:
- Observed ambipolar thermopower as Fermi energy shifts between conducting and valence bands.
- Identified phonon drag as the primary contributor to thermopower.
- Demonstrated modification of the Seebeck coefficient due to 2D electron-3D hole scattering in coexisting electronic states.
Conclusions:
- Phonon drag is the main mechanism governing thermopower in these HgTe films.
- Scattering between 2D Dirac electrons and bulk holes significantly influences the Seebeck coefficient.
- The findings provide insights into the complex thermoelectric behavior of topological insulator materials.
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