Magnetochiral tunnel junction of van der Waals multiferroic NiI2

Antiferromagnetic spintronics has garnered wide interest for its ultrafast dynamics and nearly vanishing stray field. Achieving all-electric control in antiferromagnetic spintronics is of great interest for potential ultrafast, energy-efficient and highly compact information devices. Spin spiral type-II multiferroics exhibits an inversion-symmetry-breaking antiferromagnetic order which directly induces a ferroelectric polarization, allowing for cross-control between spin chirality and electric polarization. Here we report the observation of tunnelling magnetoresistance (TMR) that can be switched by an external electric field, in a magnetochiral tunnel junction (MCTJ) consisting of two spin spiral type-II multiferroic NiI2 layers, gapped by an insulating hexagonal baron nitrode (hBN) layer. We measured a TMR ratio of around 35% between same and opposite spin chirality, in an analogy to parallel and antiparallel spin configuration in ferromagnetic tunnel junction (FMTJ). Our work lays the foundation for the development of magnetochiral spintronic devices using spin spiral type-II multiferroics.