Multi-State Memory in 2D Magnets via Thickness-Engineered Growth.

Abstract

Two-dimensional (2D) magnets offer substantial potential for high-density spintronic memory due to their tunable magnetic states, yet a robust, scalable strategy for controlling domain configurations for 2D magnets remains elusive. Here, a selective non-uniform nucleation strategy via chemical vapor deposition is proposed to achieve controlled, non-homogeneous growth of room-temperature ferromagnetic CrTe nanoflakes. This enables bottom-up control of domain evolution by leveraging the strong correlation between the thickness profile and magnetization reversal. The stepwise magnetization reversal in multi-thickness nanoflakes endows CrTe with multiple magnetic states. Utilizing such multi-thickness CrTe nanoflake, a tunable multi-state magnetoresistance is successfully realized in vertical spin valve devices. The controlled synthesis of multi-thickness CrTe nanoflakes signifies a breakthrough in domain-state control in 2D magnet, and establishes a robust material foundation for potential applications in multi-state storage and spin encryption communication.