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Abstract Searching for Kagome magnets with novel magnetic and electronic properties has been attracting significant efforts recently. Here, the magnetic, electronic, and thermoelectric properties of Fe3Ge single crystals with Fe atoms forming a slightly distorted Kagome lattice are reported. It is shown that Fe3Ge exhibits a large anomalous Hall effect and anomalous Nernst effect. The observed anomalous transverse thermoelectric conductivity reaches ≈4.6 A m−1 K−1, which is larger than the conventional ferromagnets and most of the topological ferromagnets reported in literature. The first‐principles calculations suggest that these exceptional transport properties are dominated by the intrinsic mechanism, which highlights the significant contribution of the Berry curvature of massive Dirac gaps in the momentum space. Additionally, a topological Hall resistivity of 0.9 µΩ cm and a topological Nernst coefficient of 1.2 µV K−1are also observed, which are presumably ascribed to the Berry phase associated with the field‐induced non‐zero scalar spin chirality. These features highlight the synergic effects of the Berry phases in both momentum space and real space of Fe3Ge, which render it an excellent candidate for room‐temperature thermoelectric applications based on transverse transport.
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A single crystal study of Kagome metals U 2 Mn 3 Ge and U 2 Fe 3 Ge
Abstract Single crystals of U2Mn3Ge and U2Fe3Ge with a Kagome lattice structure were synthesized using a high-temperature self-flux crystal growth method. The physical properties of these crystals were characterized through measurements of resistivity, magnetism, and specific heat. U2Fe3Ge exhibits ferromagnetic ground state and anomalous Hall effect, and U2Mn3Ge demonstrates a complex magnetic structure. Both compounds exhibit large Sommerfeld coefficient, indicating coexistence of heavy Fermion behaviour with magnetism. Our results suggest that this U2TM3Ge (TM = Mn, Fe, Co) family is a promising platform to investigate the interplay of magnetism, Kondo physics and the Kagome lattice.
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- PAR ID:
- 10510763
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Journal of Physics: Condensed Matter
- Volume:
- 36
- Issue:
- 34
- ISSN:
- 0953-8984
- Format(s):
- Medium: X Size: Article No. 345602
- Size(s):
- Article No. 345602
- Sponsoring Org:
- National Science Foundation
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