Magnetic anisotropy modulation is an effective method to simultaneously reduce the switching current and extend the data retention of magnetic tunnel junction (MTJ), which is promising to be used in the next-generation spin transfer torque (STT) magnetic random-access memory. However, to meet the requirements of high storage life and harsh environments, the improved perpendicular magnetic anisotropy of MTJ makes the conventional modulation methods suffer from high breakdown risk owing to the relatively low efficiency. In this paper, a method of phase-change controlled magnetic anisotropy (PCMA) is introduced to a physical model of VO₂/CoFeB/MgO/CoFeB perpendicular MTJ with superior modulation capability proved by systematical simulation. The time sequence of phase change pulse and STT pulse is studied, proving that there exists a specific interval to achieve both rapid and low-power switching. With the joint effect of PCMA and STT, low-energy (68.2 fJ), low-error-rate (0.08), and fast (2 ns) write operation can be achieved in the MTJ accompanied by a high thermal stability factor (78). The results demonstrate that the PCMA-STT switching strategy is most suitable for MTJ with large perpendicular magnetic anisotropy, paving a promising way to replace NOR flash memories.

中文翻译：

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垂直磁隧道结中的相变辅助自旋转移扭矩切换

磁各向异性调制是同时降低开关电流和延长磁隧道结 (MTJ) 数据保留的有效方法，有望用于下一代自旋转移矩 (STT) 磁性随机存取存储器。然而，为了满足高存储寿命和恶劣环境的要求，MTJ改进的垂直磁各向异性使得传统调制方法由于效率相对较低而遭受高击穿风险。本文将相变控制磁各向异性 (PCMA) 方法引入到 VO ₂的物理模型中/CoFeB/MgO/CoFeB 垂直 MTJ，具有经系统仿真证明的卓越调制能力。研究了相变脉冲和STT脉冲的时序，证明存在一个特定的时间间隔来实现快速和低功率切换。在 PCMA 和 STT 的共同作用下，MTJ 可以实现低能量 (68.2 fJ)、低错误率 (0.08) 和快速 (2 ns) 写入操作，同时具有高热稳定性因子 (78) . 结果表明PCMA-STT切换策略最适合具有大垂直磁各向异性的MTJ，为替代NOR闪存铺平了道路。