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Abstract The Nernst effect, the generation of a tranverse electric voltage in the presence of longitudinal thermal gradient, has garnered significant attention in the realm of magnetic topological materials due to its superior potential for thermoelectric applications. In this work, the electronic and thermoelectric transport properties of a Kagome magnet ErMn6Sn6are investigated, a compound showing an incommensurate antiferromagnetic phase followed by a ferrimagnetic phase transition upon cooling. It is shown that in the antiferromagnetic phase ErMn6Sn6exhibits both topological Nernst effect and anomalous Nernst effect, analogous to the electric Hall effects, with the Nernst coefficient reaching 1.71 µV K⁻¹ at 300 K and 3 T. This value surpasses that of most of previously reported state‐of‐the‐art canted antiferromagnetic materials and is comparable to recently reported other members of RMn6Sn6(R = rare‐earth, Y, Lu, Sc) compounds, which makes ErMn6Sn6a promising candidate for advancing the development of Nernst effect‐based thermoelectric devices.
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Enhanced Thomson and Unusual Nernst Coefficients in 1T‐ TiSe2 Due to Bipolar Transport and CDW Phase Transition
Thermoelectric coolers utilizing the Peltier effect have dominated the field of solid‐state cooling but their efficiency is hindered by material limitations. Alternative routes based on the Thomson and Nernst effects offer new possibilities. Here, we present a comprehensive investigation of the thermoelectric properties of 1T‐TiSe2, focusing on these effects around the charge density wave transition (≈200 K). The abrupt Fermi surface reconstruction associated with this transition leads to an exceptional peak in the Thomson coefficient of 450 μV K−1at 184 K, surpassing the Seebeck coefficient. Furthermore, 1T‐TiSe2exhibits a remarkably broad temperature range (170–400 K) with a Thomson coefficient exceeding 190 μV K−1, a characteristic highly desirable for the development of practical Thomson coolers with extended operational ranges. Additionally, the Nernst coefficient exhibits an unusual temperature dependence, increasing with temperature in the normal phase, which we attribute to bipolar conduction effects. The combination of solid–solid pure electronic phase transition to a semimetallic phase with bipolar transport is identified as responsible for the unusual Nernst trend and the unusually large Thomson coefficient over a broad temperature range.
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- PAR ID:
- 10568887
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ENERGY & ENVIRONMENTAL MATERIALS
- Volume:
- 8
- Issue:
- 4
- ISSN:
- 2575-0356
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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