Asymmetric Magnetization Switching and All-Electric Field-Free Programmable Spin Logic Enabled by the Interlayer Dzyaloshinskii-Moriya Interaction.

The exceptional property of the interfacial Dzyaloshinskii-Moriya interaction (DMI) is an important way to develop topologically nontrivial spin textures in two-dimensional (2D) configurations. It is of great significance for the future development of fast and energy-efficient spintronic devices. Recent pioneering works have discovered the existence of interlayer DMI in multilayer films composed of two ferromagnets separated by a nonmagnetic spacer. This effect has created an exciting opportunity for the development and application of chiral effects in three-dimensional (3D) spin structures, which could become a critical component of future multilayer spintronic devices. Here, a unique asymmetric current-driven field-free magnetization switching is observed in an orthogonal magnetization system, CoFeB/Pt/CoFe/Pt. The reason for the asymmetry is attributed to the existence of interlayer DMI. Furthermore, this structure achieves an exceptional field-free switching ratio of nearly 90%. It has been verified through tilt angle measurements that the field-free switching in this system is primarily determined by the coexistence of an antisymmetric interaction, interlayer DMI, and canted magnetization. In addition, three all-electric programmable logic gates are successfully implemented by employing this asymmetric switching behavior. This research establishes a foundation for the development of logic gates and memory devices that operate fast, with low power consumption, and are all-electric controlled.