Experimental Demonstration of NAND-Like Spin-Torque Memory Unit

Current-induced magnetization switching is crucial in high-performance nonvolatile memory especially when the spin-transfer torque (STT) and spin-orbit torque (SOT) are employed in the mainstream magnetic random-access memory. However, in STT devices, the intrinsic mechanism leads to a long write latency, a low endurance, and a high-power consumption, while in SOT devices, a three-terminal structure is necessary to complete the read and write operations, causing a low space efficiency. In this work, we experimentally demonstrate a NAND-like spin-torque memory unit with the interplay of STT and SOT. The spin joint effect induced magnetic reversal is verified to be more energy-efficient and faster than that of STT. It also shows a great selectivity to ensure the reliability of the write operation. The memory unit, containing 8 magnetic tunnel junctions with a shared heavy-metal nanowire, is erased by a single SOT current and written by the combination of STT and SOT, showing the great potential for the high-density, ultrafast and energy efficient memory applications.