Lee Seong-Hyub, Kim Myeonghoe, Whang Hyun-Seok, Nam Yune-Seok, Park Jung-Hyun, Kim Kitae, Kim Minhwan, Shin Jiho, Yu Ji-Sung, Yoon Jaesung, Chang Jun-Young, Kim Duck-Ho, Choe Sug-Bong
Department of Physics and Astronomy, Seoul National University, Seoul, 08826, Republic of Korea.
Center for Spintronics, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.
Nat Commun. 2023 Nov 23;14(1):7648. doi: 10.1038/s41467-023-43468-9.
Magnetic domain-wall devices such as racetrack memory and domain-wall shift registers facilitate massive data storage as hard disk drives with low power portability as flash memory devices. The key issue to be addressed is how perfectly the domain-wall motion can be controlled without deformation, as it can replace the mechanical motion of hard disk drives. However, such domain-wall motion in real media is subject to the stochasticity of thermal agitation with quenched disorders, resulting in severe deformations with pinning and tilting. To sort out the problem, we propose and demonstrate a new concept of domain-wall control with a position error-free scheme. The primary idea involves spatial modulation of the spin-orbit torque along nanotrack devices, where the boundary of modulation possesses broken inversion symmetry. In this work, by showing the unidirectional motion of domain wall with position-error free manner, we provide an important missing piece in magnetic domain-wall device development.
诸如赛道存储器和畴壁移位寄存器之类的磁畴壁器件有助于实现海量数据存储，兼具硬盘驱动器的大容量和闪存设备的低功耗便携性。需要解决的关键问题是如何在不产生变形的情况下完美控制畴壁运动，因为它可以替代硬盘驱动器的机械运动。然而，在实际介质中，这种畴壁运动受到热涨落和猝灭无序的随机性影响，导致严重的钉扎和倾斜变形。为了解决这个问题，我们提出并演示了一种具有无位置误差方案的畴壁控制新概念。主要思想是沿着纳米轨道器件对自旋轨道转矩进行空间调制，其中调制边界具有破缺的反演对称性。在这项工作中，通过展示畴壁以无位置误差的方式单向运动，我们为磁畴壁器件的发展提供了重要的缺失环节。
