Interfacial magnetic coupling in CrI3/CrBr3 heterostructures via tunneling magnetoresistance.

Two-dimensional (2D) magnetic materials and their van der Waals (vdW) heterostructures offer a unique platform for investigating low-dimensional magnetic interactions and developing next-generation spintronic devices. This study employs electronic tunneling spectroscopy to systematically explore the interfacial magnetic coupling mechanisms in CrI3/CrBr3 vdW heterostructures. Experimentally, we observe complex tunneling magnetoresistance (TMR) behaviors, including multi-step jumps and asymmetric hysteresis, with their magnetic origins confirmed through temperature-dependent measurements. Theoretically, we develop a one-dimensional (1D) spin-chain model that successfully reproduces the TMR characteristics, unveiling the synergistic role of interfacial Dzyaloshinskii-Moriya interaction (DMI, ∼10.8 μeV) and ferromagnetic exchange (∼13.5 μeV) in governing magnetic configurations. We find that interfacial DMI, driven by broken inversion symmetry, induces spin canting in the ferromagnetic layers, profoundly influencing TMR behavior. This work not only provides a novel physical framework for understanding interfacial coupling in vdW magnetic heterostructures but also charts a pathway for designing multi-state memory devices through interfacial engineering.