Room-temperature Ferromagnetism, Perpendicular Magnetic Anisotropy, and Anisotropic Magnetoresistance in Epitaxially Stabilized Air-stable Chromium Tellurides

Chromium telluride (Cr _(1+δ) Te ₂ ) thin films of various δ were prepared using a hybrid pulsed laser deposition technique by varying the flux rate of a Te-molecular beam source. We found that the thickness and nanocrystalline quality of the films increased with the Te-flux. All three films prepared showed hexagonal layering with the same out-of-plane lattice constant. Increasing the Te-flux rate stabilized the CrTe, Cr ₂ Te ₃ , and CrTe ₂ phases of the telluride, and they showed different magnetic transition temperatures (T _C ) from film to film, corresponding to their composition. The tellurides show anisotropic magnetoresistance (AMR) and a metal-to-insulator transition (MIT) at the vicinity of their respective T _C s, with the highest T _C of 324 K unveiled by Cr ₂ Te ₃ . These stoichiometry-controlled room-temperature ferromagnetic air-stable 2D materials prepared using the hybrid deposition technique can significantly advance further development of 2D materials for magnetic device applications.