High-performance van der Waals MTJs with graphene barrier and Fe3GaTe2 electrodes

Abstract

Van der Waals (vdW) magnetic tunnel junctions (MTJs) have emerged as promising candidates for next-generation spintronic devices, offering superior interface quality and interlayer coupling that enable efficient spin transport and ultra-low-power memory. In this study, we investigate spin transport properties in vdW Fe3GaTe2/graphene/Fe3GaTe2 MTJs using first-principles calculations combined with the non-equilibrium Green's function method. Our results demonstrate that the transport mechanism in these MTJs is dominated by quantum tunneling. The vdW MTJ with monolayer graphene exhibits a high spin filtering efficiency close to 100%, an exceptionally giant tunneling magnetoresistance (TMR) of 8.85 × 106%, and an ultra-low resistance-area product of 0.051 Ω μm2, significantly outperforming traditional bulk oxide MTJs. Our detailed device-based analysis further confirms that the giant TMR originates from the high spin polarization of Fe3GaTe2 electrodes. Our findings provide valuable insights for designing high-performance vdW spintronic devices.