LAUSR

Significance States of matter are traditionally classified by their symmetry, as exemplified by the distinction between a solid and a liquid. Topological quantum phases, on the other hand, are harder to characterize, and still harder to identify. This is especially so in electronic systems with strong correlations. In this work, we uncover a purely electric-field-driven “giant” Hall response—orders of magnitude above expectation—in one such material and propose a mechanism whereby it is driven by strong correlations. Our results will enable the identification of electronic topological states in a broad range of strongly correlated quantum materials and may trigger efforts toward their exploitation in robust quantum electronics. Nontrivial topology in condensed-matter systems enriches quantum states of matter to go beyond either the classification into metals and insulators in terms of conventional band theory or that of symmetry-broken phases by Landau’s order parameter framework. So far, focus has been on weakly interacting systems, and little is known about the limit of strong electron correlations. Heavy fermion systems are a highly versatile platform to explore this regime. Here we report the discovery of a giant spontaneous Hall effect in the Kondo semimetal Ce3Bi4Pd3 that is noncentrosymmetric but preserves time-reversal symmetry. We attribute this finding to Weyl nodes—singularities of the Berry curvature—that emerge in the immediate vicinity of the Fermi level due to the Kondo interaction. We stress that this phenomenon is distinct from the previously detected anomalous Hall effect in materials with broken time-reversal symmetry; instead, it manifests an extreme topological response that requires a beyond-perturbation-theory description of the previously proposed nonlinear Hall effect. The large magnitude of the effect in even tiny electric and zero magnetic fields as well as its robust bulk nature may aid the exploitation in topological quantum devices.