Deterministic field-free voltage-induced magnetization switching with self-regulated precession for low-power memory

Abstract

Spintronic devices are regarded as a promising solution for future computing and memory technologies. They are non-volatile, resilient to radiation, and compatible with the CMOS back-end process. However, the major drawbacks of modern current-driven spintronic devices are the long switching delay and relatively high power consumption. Recent progress in magnetoelectronics, particularly in voltage-controlled magnetism reveals a possible solution. Voltage-controlled magnetic anisotropy (VCMA) allows the manipulation of interface-mediated perpendicular anisotropy energy. However, most VCMA-based switching methods require pre-read operation, precise pulse-width control and have high write error rate. This study proposes a novel deterministic self-regulated precessional ferromagnet switching method, which overcomes these issues. In the discussed method, energy symmetry is broken by a dependence of MTJ resistance on the angle between magnetization vectors of free and pinned layers. Hence, the method does not require an external magnetic field and large electric current. The proposed method is verified through micromagnetic simulations and benchmarked with other methods typically reported in the literature. We report the write error rate is significantly improved compared to other VCMA switching methods. Moreover, the mean energy consumption is as low as 38.22 fJ and the mean switching delay is 3.77 ns. © 2023, Springer Nature Limited.