Thermally‐Stable Temperature‐Independent Tunneling Magnetoresistance in all van der Waals Fe₃GaTe₂/GaSe/Fe₃GaTe₂ Magnetic Tunnel Junctions

Thermal stability is of great significance for the next-generation two-dimensional (2D) non-volatile spintronic devices. Typically, as the temperature increases, the spin polarization of materials decreases rapidly following the Bloch 𝑇^3/2 law in low-temperature regions, resulting in a rapid decrease in the tunneling magnetoresistance (TMR) of the magnetic tunnel junction (MTJ). Owing to the thermal effects induced by current during the writing processes, even small temperature fluctuations can result in significant variations in the TMR of MTJs, hindering their practical applications. In this paper, all-van der Waals Fe₃GaTe₂/GaSe/Fe₃GaTe₂ (FGaT/GaSe/FGaT) MTJ devices are constructed, achieving a TMR ratio of 47% at low temperatures and 17% at room temperature. Importantly, the TMR ratio remains stable within a temperature range from 2 to 160 K, breaking the Bloch 𝑇^3/2 law. The temperature-independent TMR is highly related to the enhanced perpendicular magnetic anisotropy (PMA) with reduced dimensionality is demonstrated. This work paves a promising path to achieve high-performance, thermally stable 2D spintronic memory chips.