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arXiv · 2010.07864

Emergent topological fields and relativistic phonons within the thermoelectricity in topological insulators

Abstract

Topological edge states are predicted to be responsible for the high efficient thermoelectric response of topological insulators, currently the best thermoelectric materials. However, to explain their figure of merit the coexistence of topological electrons, entropy and phonons can not be considered independently. In a background that puts together electrodynamics and topology, through an expression for the topological intrinsic field, we treat relativistic phonons within the topological surface showing their ability to modulate the Berry curvature of the bands and then playing a fundamental role in the thermoelectric effect. Finally, we show how the topological insulators under such relativistic thermal excitations keep time reversal symmetry allowing the observation of high figures of merit at high temperatures. The emergence of this new intrinsic topological field and other constraints are suitable to have experimental consequences opening new possibilities of improving the efficiency of this topological effect for their based technology.

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Daniel Faílde, Daniel Baldomir. 2020-10-15. Emergent topological fields and relativistic phonons within the thermoelectricity in topological insulators. https://doi.org/10.1038/s41598-021-93667-x

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