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Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
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Thermoelectric Transport Driven by the Hilbert-Schmidt Distance
Chang-Geun Oh1, Kun Woo Kim2, Jun-Won Rhim3,4
1Department of Applied Physics, The University of Tokyo, Tokyo, 113-8656, Japan.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|November 18, 2024
Summary
Quantum geometry significantly impacts thermoelectric performance. The Hilbert-Schmidt distance of Bloch wavefunctions, a measure of quantum distance, can double the thermoelectric power factor in materials, enhancing device efficiency.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Bloch wavefunctions are fundamental to understanding electronic properties.
- Electronic transport and thermoelectric performance are critical for energy applications.
- Quantum geometric properties, such as Berry curvature, are known to influence material characteristics.
Purpose of the Study:
- To investigate the role of quantum geometric characteristics, specifically the Hilbert-Schmidt distance of Bloch wavefunctions, in thermoelectric performance.
- To establish a connection between quantum distance distribution and electronic transport scattering rates.
- To explore the impact of quantum geometry on thermoelectric power factors in specific material systems.
Main Methods:
- Utilized the Boltzmann equation framework to model electronic transport.
- Quantified the influence of Hilbert-Schmidt distance on thermoelectric properties.
- Analyzed the relationship between quantum distance on the Fermi surface and scattering rates with magnetic and nonmagnetic impurities.
- Applied the general formulation to isotropic quadratic band-touching semimetals.
Main Results:
- Thermoelectric performance is significantly influenced by the Hilbert-Schmidt distance of Bloch wavefunctions.
- A direct link was found between the distribution of quantum distance on the Fermi surface and the electronic transport scattering rate.
- The thermoelectric power factor can be expressed in terms of the maximum quantum distance (d_max).
- A doubling of the power factor was observed when d_max reached one, compared to trivial geometry (d_max = 0).
Conclusions:
- Quantum geometry, beyond Berry curvature, plays a vital role in electronic transport and thermoelectric properties.
- The Hilbert-Schmidt distance of Bloch wavefunctions is a key factor for optimizing thermoelectric materials.
- These findings provide a pathway for designing and improving thermoelectric devices through control of quantum geometric effects.
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