Colossal anomalous Nernst effect in a correlated noncentrosymmetric kagome ferromagnet
ORAL
Abstract
Analogous to the Hall effect, the Nernst effect is the generation of a transverse voltage due
to a temperature gradient in the presence of a perpendicular magnetic field. The Nernst effect
has promise for thermoelectric applications and as a probe of electronic structure. In magnetic
materials, a so-called anomalous Nernst effect (ANE) is possible in a zero magnetic field. We
report a large ANE in a kagome ferromagnetic uranium compound. Uranium's
5f electrons provide strong electronic correlations that lead to narrow bands, which are a known
route to producing a large thermoelectric response. Additionally, the large nuclear charge of
uranium generates strong spin-orbit coupling, which produces an intrinsic transverse response
in this material due to the Berry curvature associated with the relativistic electronic structure.
Furthermore, theoretical calculations show that numerous Weyl points and nodes exist within the vicinity of the Fermi level. This work demonstrates that magnetic actinide materials
can host strong Nernst and Hall responses due to their combined correlated and topological nature.
to a temperature gradient in the presence of a perpendicular magnetic field. The Nernst effect
has promise for thermoelectric applications and as a probe of electronic structure. In magnetic
materials, a so-called anomalous Nernst effect (ANE) is possible in a zero magnetic field. We
report a large ANE in a kagome ferromagnetic uranium compound. Uranium's
5f electrons provide strong electronic correlations that lead to narrow bands, which are a known
route to producing a large thermoelectric response. Additionally, the large nuclear charge of
uranium generates strong spin-orbit coupling, which produces an intrinsic transverse response
in this material due to the Berry curvature associated with the relativistic electronic structure.
Furthermore, theoretical calculations show that numerous Weyl points and nodes exist within the vicinity of the Fermi level. This work demonstrates that magnetic actinide materials
can host strong Nernst and Hall responses due to their combined correlated and topological nature.
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Presenters
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Tomoya Asaba
- Los Alamos National laboratory
- University of Michigan