First-principles theory of ionic thermoelectricity
Abstract
Symmetry plays a crucial role in shaping the theories of fundamental forces. For example, general covariance -- the equivalence of all possible coordinate systems of spacetime -- dictates the law of gravity. Here, we extend this concept to nonequilibrium thermodynamics by developing a theory of ionic thermoelectricity (thermoelectricity without electrons) in electronically gapped ionic conductors. Within the Green-Kubo formalism, we show that energy gauge invariance -- the equivalence of all possible ways of distributing energy among atoms -- primarily determines the expressions for ionic thermoelectric coefficients. This symmetry-dictated theory is generally applicable, regardless of specific ion transport mechanisms, and provides a rigorous conceptual and computational framework for describing ionic thermoelectricity from first principles.
Cite
@article{arxiv.2503.05278,
title = {First-principles theory of ionic thermoelectricity},
author = {Byeoksong Lee and Joongoo Kang},
journal= {arXiv preprint arXiv:2503.05278},
year = {2025}
}