Large anomalous transverse transport properties in atomically thin 2D Fe3GaTe2

Abstract

Anomalous transverse conductivities, such as anomalous Hall conductivity (AHC), anomalous Nernst conductivity (ANC), and anomalous thermal Hall conductivity (ATHC), play a crucial role in the emerging field of spintronics. Motivated by the recent fabrication of two-dimensional (2D) ferromagnetic thin film Fe₃GaTe₂, we investigate the thickness-dependent anomalous transverse conductivities of the 2D Fe₃GaTe₂ system (from one to four layers). The atomically ultrathin 2D Fe₃GaTe₂ system shows above-room-temperature ferromagnetism with a large perpendicular magnetic anisotropy energy. Furthermore, we obtain a large AHC of −485 S/cm in the four-layer thickness, and this is further enhanced to −550 S/cm with small electron doping. This AHC is seven times larger than the measured AHC in thicker 2D Fe₃GaTe₂ (178 nm). The ANC also reaches 0.55 A/K.m in the four-layer structure. Along with these, the four-layer system exhibits a large ATHC (−0.105 ~ −0.135 W/K.m). This ATHC is comparable to the large ATHC found in Weyl semimetal Co₃Sn₂S₂. Based on our results, the atomically ultrathin 2D Fe₃GaTe₂ system shows outstanding anomalous transverse conductivities and can be utilized as a potential platform for future spintronics and spin caloritronic device applications.