Elucidation of the mechanism for maintaining ultrafast domain wall mobility over a wide temperature range
Elucidation of the mechanism for maintaining ultrafast domain wall mobility over a wide temperature range
复制标题
阐明在宽温度范围内保持超快畴壁迁移率的机制
DOI：
10.1039/d2ma00273f
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发表时间：
2022
影响因子：
5
通讯作者：
Awano H.
中科院分区：
文献类型：
--
作者：
Ranjbar S.;Kambe S.;Sumi S.;Thach P. V.;Nakatani Y.;Tanabe K.;Awano H.
为了使用即将到来的5G通信标准实现20 Gbps的数据速率，识别1200 m s−1的域壁（DW）速度（vDW）至关重要。我们展示了在富铁GdFeCo磁线中，在270至350 K的宽温度范围内，在低电流密度下实现1200 m s−1 DW速度的潜在方法。我们发现了vDW与脉冲持续宽度之间的显著关系，这对应于焦耳热效应和DW的形状。通常，如果电流密度一定，则电流驱动的DW位移与脉冲宽度成正比，因此DW速度也一定。我们发现vDW随外加脉冲电流宽度的缩短而增大。然而，在长脉冲持续宽度的情况下，DW形状呈现圆形。因此，类阻尼有效场与Neel DW除在线材中心处外均不正交；随着SOT效率的降低，DW速度降低。我们还测量了Dzyaloshinskii-Moriya相互作用（DMI）场在3 ns 30 ns脉冲持续宽度。在30ns的情况下，与3ns的宽度相比，DMI场被发现减半。一般来说，DMI场是一个特定于材料的参数，这种差异通过电流驱动的DW形状来澄清。我们关于补偿铁磁材料在低电流密度下DW运动的快速和高热稳定性的发现为高速自旋电子器件开辟了新的机会。
To achieve a 20 Gbps data rate using the upcoming 5G communication standard, it is crucial to recognize a domain wall (DW) velocity (vDW) of 1200 m s−1. We demonstrate a potential means of achieving the DW speed of 1200 m s−1 at low current density in a wide temperature range from 270 to 350 K in Fe-rich GdFeCo magnetic wire. We show a significant relationship between the vDW and the pulse duration width, which corresponds to the Joule heating effect and the shape of the DW. Generally, if the current density is constant, the current-driven DW displacement is proportional to the pulse width, so the DW speed is also constant. We found that the vDW increases with the shortening of the applied pulse current width. However, the DW shape appears rounded in the case of long pulse duration width. Accordingly, the damping-like effective field and the Neel DW are not orthogonal to each other except in the wire center; as the efficiency of SOT decreases, the DW speed reduces. We also measured the Dzyaloshinskii–Moriya interaction (DMI) field for 3 ns 30 ns pulse duration widths. In the case of 30 ns, the DMI field was found halved in comparison to the 3 ns width. Generally, the DMI field is a material-specific parameter, and this difference is clarified by the shape of the DW driven by the current. Our findings on the fast and high thermal stability of DW motion at low current density in compensated ferrimagnetic material open new opportunities for high-speed spintronic devices.