Band-driven switching of magnetism in a van der Waals magnetic semimetal.

Magnetic semimetals form an attractive class of materials because of the nontrivial contributions of itinerant electrons to magnetism. Because of their relatively low-carrier-density nature, a doping level of those materials could be largely tuned by a gating technique. Here, we demonstrate gate-tunable ferromagnetism in an emergent van der Waals magnetic semimetal CrTe based on an ion-gating technique. Upon doping electrons into the system, the Curie temperature () sharply increases, approaching near to room temperature, and then decreases to some extent. This non-monotonous variation of accompanies the switching of the magnetic anisotropy, synchronously followed by the sign changes of the ordinary and anomalous Hall effects. Those results clearly elucidate that the magnetism in CrTe should be governed by its semimetallic band nature.