Rich unconventional Hall effects in a single quasi-kagome Kondo Weyl semimetal candidate Ce3TiSb5

It is generally believed that electronic correlation, geometric frustration, and topology, individually, can facilitate the emergence of various intriguing properties that have attracted a broad audience for both fundamental research and potential applications. Here, we report a series of unconventional Hall effects observed in a single compound—quasi-kagome Kondo Weyl semimetal candidate Ce3TiSb5. In the paramagnetic phase, signature of dynamic c-f hybridization is revealed by a reduction of anomalous Hall effect and is connected to frustration-promoted incoherent Kondo scattering. A large topological Hall effect exceeding 0.2 μΩ ⋅ cm is found at low temperatures, which should be ascribed to the non-collinear magnetic texture. In addition, a peculiar loop-shaped Hall effect with switching chirality is also seen, which is inferred to be associated with magnetic domain walls that pin history-dependent spin chirality and/or Fermi-arc surface states projected from the in-gap Weyl nodes. These exotic results place Ce3TiSb5 in a regime of highly-frustrated antiferromagnetic dense Kondo lattice with a nontrivial topology on an “extended” global phase diagram, and highlight the interplay among electronic correlation, geometric frustration and topology. Electronic correlation, geometric frustration, and topology are known to individually drive intriguing properties in materials. Here, the authors explore these interactions in the quasi-kagome Kondo Weyl semimetal Ce3TiSb5, revealing unconventional Hall effects that underscore the complex interplay of these factors, with implications for understanding topological and magnetic phenomena