Two-Dimensional Cr3Te4/WS2/Fe3GeTe2/WTe2 Magnetic Memory with Field-Free Switching and Low Power Consumption.

Spin-orbit torque (SOT) magnetic memory technology has garnered significant attention due to its ability to enable field-free switching of magnets with strong perpendicular magnetic anisotropy (PMA). However, concerns regarding power consumption of SOT-memory are persisting. Here, this work proposes a method to construct magnetic tunnel junction (MTJ) by transferring chemically vapor-deposited two-dimensional (2D) Cr3Te4/WS2 van der Waals (vdW) heterostructures onto 2D Fe3GeTe2 (FGT) magnet. The robustness and tunability of 2D magnets allow MTJs to exhibit non-volatility, multiple output states, and impressive cycling durability. MTJs with thin WS2 barriers (fewer than six layers) exhibit a linear tunneling effect, achieving a low resistance-area product (RA) of 15.5 kΩ·µm2 using bilayer WS2, which facilitats low-power operation. Furthermore, the different 2D magnets display a significant anti-parallel window of up to 8 kOe. SOT-memory based on the typical MTJ demonstrates a low write consumption of 0.3 mJ and read consumption of 9.7 nJ, marking a significant advancement in 2D vdW SOT-memory. This research has pointed out a new direction for constructing low power consumption SOT-memory with PMA field-free switching.