Anomalous Thomson Effect

Abstract

We formulate an effect called the anomalous Thomson effect (ATE), which constitutes the Thomson counterpart to the anomalous Hall effect and anomalous Nernst effect (ANE). The anomalous Thomson coefficient (ATC) is derived as a function of the anomalous Nernst coefficient (ANC); This relation is model independent within local linear response and holds for the total anomalous Nernst coefficient, irrespective of whether its microscopic origin is intrinsic or extrinsic. Specifically, we study a massive Dirac model for Fe3Sn2 to capture intrinsic Berry-curvature-driven transport, where the Berry curvature near the gapped Dirac cones enhances ATC, and we also deduce the ATC from measured anomalous Nernst data reported for CoS2, Co3Sn2S2, and CeCrGe3. In the low-temperature limit, the ratio ATC/ANC approaches three, and 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 formulated ATE can be directly verified using existing ANE data, without the need for additional equipment or measurements.

7 pages, 3 figures