Thermoelectric effects in two-dimensional topological insulators

Z. Z. Alisultanov; E. G. Idrisov; A. V. Kavokin

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arXiv · 2502.20888

Thermoelectric effects in two-dimensional topological insulators

Z. Z. Alisultanov·E. G. Idrisov·A. V. Kavokin

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Abstract

We explore the nontrivial thermoelectric properties of two-dimensional topological systems. For the Chern insulator, we show that the Seebeck coefficient is fully determined by the Kelvin formula, while the Nernst coefficient vanishes. For a two-dimensional electron gas with Rashba spin-orbit interactions we reveal how the Berry curvature affects the thermoelectric coefficients, and derive the Mott-like equation for thermopower. We predict a strong variation of the thermopower of a two-dimensional topological insulator with time-reversal symmetry in the ballistic and dissipative regimes. The Kelvin formula applies in the ballistic regime, while the Mott formula holds in the dissipative regime. Importantly, in a system with trapezoidal geometry, the combination of ballistic and dissipative regimes leads to the anomalous Nernst effect. Finally, we analyze a two-dimensional Anderson insulator, where edge modes show distinct temperature behavior of the Seebeck coefficient near the weak localization-strong localization transition temperatures. In the trivial phase, the thermopower exhibits a strong power law temperature dependence, while in the topological phase both power law and exponential dependences coexist.

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Z. Z. Alisultanov, E. G. Idrisov, A. V. Kavokin. 2025-02-28. Thermoelectric effects in two-dimensional topological insulators. https://arxiv.org/abs/2502.20888

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