Kang Doo Hyung, Shin Mincheol
School of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, South Korea.
Sci Rep. 2021 Nov 24;11(1):22842. doi: 10.1038/s41598-021-02185-3.
Recently, magnetic tunnel junctions (MTJs) with shape perpendicular magnetic anisotropy (S-PMA) have been studied extensively because they ensure high thermal stability at junctions smaller than 20 nm. Furthermore, spin-transfer torque (STT) and spin-orbit torque (SOT) hybrid switching, which guarantees fast magnetization switching and deterministic switching, has recently been achieved in experiments. In this study, the critical switching current density of the MTJ with S-PMA through the interplay of STT and SOT was investigated using theoretical and numerical methods. As the current density inducing SOT ([Formula: see text]) increases, the critical switching current density inducing STT ([Formula: see text]) decreases. Furthermore, for a given [Formula: see text], [Formula: see text] increases with increasing thickness, whereas [Formula: see text] decreases as the diameter increases. Moreover, [Formula: see text] in the plane of thickness and spin-orbit field-like torque ([Formula: see text]) was investigated for a fixed [Formula: see text] and diameter. Although [Formula: see text] decreases with increasing [Formula: see text], [Formula: see text] slowly increases with increasing thickness and increasing [Formula: see text]. The power consumption was investigated as a function of thickness and diameter at the critical switching current density. Experimental confirmation of these results using existing experimental techniques is anticipated.
最近,具有垂直磁各向异性形状(S-PMA)的磁性隧道结(MTJ)受到了广泛研究,因为它们在小于20纳米的结中能确保高热稳定性。此外,自旋转移力矩(STT)和自旋轨道力矩(SOT)混合开关,其保证了快速磁化翻转和确定性翻转,最近已在实验中实现。在本研究中,使用理论和数值方法研究了通过STT和SOT相互作用的具有S-PMA的MTJ的临界翻转电流密度。随着感应SOT的电流密度([公式:见原文])增加,感应STT的临界翻转电流密度([公式:见原文])降低。此外,对于给定的[公式:见原文],[公式:见原文]随厚度增加而增加,而[公式:见原文]随直径增加而减小。此外,针对固定的[公式:见原文]和直径,研究了厚度平面内的[公式:见原文]和类自旋轨道场力矩([公式:见原文])。尽管[公式:见原文]随[公式:见原文]增加而减小,但[公式:见原文]随厚度增加和[公式:见原文]增加而缓慢增加。在临界翻转电流密度下,研究了功耗与厚度和直径的函数关系。预计将使用现有实验技术对这些结果进行实验验证。