Current-induced anomalous Hall effect and nonlinear magnetoelectric effect in the Weyl semimetal WTe2

We report the observation of a current-induced anomalous Hall effect (AHE) and a nonlinear magnetoelectric effect in few-layer WTe2 Weyl semimetal devices, achieved through independent magnetization generation and Hall measurements conducted in the absence of an external magnetic field. A direct current (dc) is used to induce out-of-plane magnetization via the magnetoelectric effect, breaking time-reversal symmetry, while an alternating current (ac) is applied for Hall measurements. The Hall resistance exhibits a quadratic dependence on the applied dc, indicating that the current induces a quadratic increase in magnetization, a phenomenon not observed in previous experiments. By employing multiple electrode pairs arranged in a circular configuration, we reveal significant anisotropy in the magnetoelectric response, which aligns with the third-order nonlinear Hall effect and is attributed to Berry connection polarizability (BCP) tensors. These findings deepen our understanding of BCP-driven magnetoelectric effects and transport phenomena in quantum materials.