Room-Temperature Magnetic Skyrmions and Large Topological Hall Effect in Chromium Telluride Engineered by Self-Intercalation

Room-temperature magnetic skyrmion materials exhibiting robust topological Hall effect (THE) are crucial for novel nano-spintronic devices. However, such skyrmion-hosting materials are rare in nature. In this study, we report a self-intercalated transition metal dichalcogenide Cr1+xTe2 with a layered crystal structure that hosts room-temperature skyrmions and exhibits large THE. By tuning the self-intercalate concentration, a monotonic control of Curie temperature from 169 to 333 K and a magnetic anisotropy transition from out-of-plane to in-plane configuration were achieved. Based on the intercalation engineering, room-temperature skyrmions were successfully created in Cr1.53Te2 with a Curie temperature of 295 K and a relatively weak perpendicular magnetic anisotropy. Remarkably, a skyrmion-induced topological Hall resistivity as large as ∼106 nΩ cm was observed at 290 K. Moreover, a sign reversal of THE was also found at low temperatures, which could be ascribed to other topological spin textures having an opposite topological charge to that of the skyrmions. Therefore, chromium telluride could be a new paradigm of the skyrmion material family with promising prospects for future device applications.