Coexisting Ferromagnetic-Antiferromagnetic State and Giant Anomalous Hall Effect in Chemical Vapor Deposition-Grown 2D Cr₅Te₈.

Abstract

Two-dimensional (2D) magnets, as an important member of the 2D material family, have emerged as a promising platform for spintronic devices. Herein, we report the chemical vapor deposition (CVD) growth of highly crystalline submillimeter-scale self-intercalated metallic 2D ferromagnetic (FM) trigonal chromium telluride (Cr₅Te₈) flakes on inert mica substrates. Through magneto-optical and magnetotransport measurements, we unveil the exceptional magnetic properties of these 2D flakes. The trigonal Cr₅Te₈ flakes exhibit a strong anisotropic FM order with a Curie temperature above 220 K. Notably, an emergent antiferromagnetic (AFM) state is observed in the MOKE signal from ultrathin Cr₅Te₈ flakes around the Curie temperature. The AFM state has a relatively weak interlayer exchange coupling, allowing a switching between the interlayer AFM and FM states by tuning the temperature. Meanwhile, the trigonal Cr₅Te₈ flakes exhibit a giant anomalous Hall effect (AHE), with an anomalous Hall conductivity of 710 Ω^-1 cm^-1 and an anomalous Hall angle of 3.5% at zero magnetic field, surpassing typical itinerant ferromagnets. Further analysis suggests that the AHE in trigonal Cr₅Te₈ is primarily driven by the skew-scattering mechanism rather than the intrinsic or extrinsic side-jump mechanism. These findings demonstrate the potential of CVD-grown ultrathin Cr₅Te₈ flakes as a promising 2D magnetic material with exceptional AHE properties for future spintronic applications.