Anomalous Hall effect in one monolayer cobalt with electrical manipulation

We investigate electrical manipulation of magnetism in Ta/Pd/Co/HfO2 films probed by anomalous Hall Effect (AHE). The coercivity of the one monolayer cobalt and the transition temperature for the disappearance of usual AHE curves could be modified by a low voltage below ±2 V via the usage of ionic liquid. The unexpected emergence of inverted Hall loops above the transition temperature but far below the Curie temperature performed on the magnetometer could be explained by the competition between skew scattering and intrinsic/side-jump contributions of AHE. Our finding provides a different avenue for exploring the origin of AHE by electrical manipulation. •Coercivity of one monolayer cobalt is modified by ionic liquid gating.•Transition temperature of anomalous Hall effect is tuned by ionic liquid gating.•Unexpected inverted Hall loops above the transition temperature are observed.•It provides a way for exploring anomalous Hall effect by electrical control.