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arXiv · 1803.03609

Thermoelectric performance of topological boundary modes

Abstract

We investigate quantum transport and thermoelectrical properties of a finite-size Su-Schrieffer-Heeger model, a paradigmatic model for a one-dimensional topological insulator, which displays topologically protected edge states. By coupling the model to two fermionic reservoirs at its ends, we can explore the non-equilibrium dynamics of the system. Investigating the energy-resolved transmission, the current and the noise, we find that these observables can be used to detect the topologically non-trivial phase. With specific parameters and asymmetric reservoir coupling strengths, we show that we can dissipatively prepare the edge states as stationary states of a non-equilibrium configuration. In addition, we point out that the edge states can be exploited to design a refrigerator driven by chemical work or a heat engine driven by a thermal gradient, respectively. These thermal devices do not require asymmetric couplings and are topologically protected against symmetry-preserving perturbations. Their maximum efficiencies significantly exceed that of a single quantum dot device at comparable coupling strengths.

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BibTeXRIS

Sina Böhling, Georg Engelhardt, Gloria Platero, Gernot Schaller. 2018-03-09. Thermoelectric performance of topological boundary modes. https://doi.org/10.1103/physrevb.98.035132

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