Anomalous Thomson Effect

TL;DR

The paper introduces the anomalous Thomson effect (ATE), a new thermoelectric phenomenon related to Berry curvature, with potential applications in solid-state refrigeration, and demonstrates its relation to the anomalous Nernst effect (ANE).

Contribution

It derives the anomalous Thomson coefficient from the anomalous Nernst coefficient and shows how ATE can be inferred from existing ANE data for various materials.

Findings

ATC is generally larger than ANC, especially at low temperatures.

The ratio ATC/ANC approaches three as temperature approaches zero.

CeCrGe3 exhibits an ATC up to fifteen times larger than ANC in liquid nitrogen temperatures.

Abstract

We propose an effect named the anomalous Thomson effect (ATE), analogous to the anomalous Hall effect and the anomalous Nernst effect (ANE). The anomalous Thomson coefficient (ATC) is derived as a function of the anomalous Nernst coefficient (ANC); hence, the ATC inherits the same mechanisms of the ANC. Specifically, we study a massive Dirac model for Fe3Sn2 to capture intrinsic Berry-curvature-driven transport. Our results show that the ATC is generally enhanced relative to the ANC. In the low-temperature limit, the ratio ATC/ANC approaches three. Since the relation between the ATE and the ANE is model-independent, we utilize experimental ANE data to infer experiment-related ATC for CoS2, Co3Sn2S2, and CeCrGe3. We find that the ATC for CeCrGe3 can be as large as fifteen times the ANC in the liquid-nitrogen temperature regime, making this effect highly attractive for solid-state thermoelectric refrigeration in this temperature range. It is important to emphasize that the proposed ATE can be directly verified using existing ANE data, without the need for additional equipment or measurements.