Anisotropic anomalous Hall effect in distorted kagome GdTi 3 Bi 4

Topological kagome magnets offer a rich landscape for exploring the intricate interplay of quantum interactions among geometry, topology, spin, and correlation. GdTi 3 Bi 4 crystallizes in layered Ti-based kagome nets intertwined with zigzag Gd chains along the a axis and orders antiferromagnetically below ∼ 15 K . Here, we present the temperature- and field-dependent electrical transport of GdTi 3 Bi 4 in different directions. The material exhibits anomalous Hall conductivity (AHC) of 410 Ω − 1 c m − 1 at 2 K for μ 0 H ∥ c , and it is completely absent for μ 0 H ∥ a , despite the similar magnetizations observed in both orientations. This behavior is quite contradictory, as the anomalous Hall effect (AHE) typically scales with the magnetization. Through first-principles calculations, it is demonstrated that in the presence of time-reversal symmetry broken by the Gd 4 f sublattice and spin-orbit coupling, the magnetization direction controls the orbital mixing in the Ti t 2 g bands, relocating Berry-curvature hot spots and producing the observed orientation-selective AHC. The results establish GdTi 3 Bi 4 as a platform for investigating new avenues of the AHE, such as directional AHE, and thus shed light on the intricate coupling between magnetic and electronic structures, paving the way for exploring novel quantum phenomena.