Li Yaojin, Zha Xi, Zhao Yifan, Lu Qi, Li Boyan, Li Chunlei, Zhou Ziyao, Liu Ming
Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education & International Center for Dielectric Research, School of Electronics and Information Engineering, the International Joint Laboratory for Micro/Nano Manufacturing and Measurement Technology, Xi'an Jiaotong University, Xi'an 710049, China.
ACS Nano. 2022 Aug 23;16(8):11852-11861. doi: 10.1021/acsnano.2c00093. Epub 2022 Jul 31.
Spin-orbit torque (SOT) efficiency is one of the key issues of spintronics. However, enhancing the SOT efficiency is usually limited by the positive correlation between resistivity and the spin Hall ratio, where a high resistivity often accompanies a large spin Hall ratio. Here, we demonstrate that sub-nanometer β-W intercalation has a considerable impact on the SOT efficiency in α-W (6 nm)/Co (8 nm)/Pt (3 nm) samples. The damping-like SOT efficiency per unit current density, ξ, of α-W (5.7 nm)/β-W (0.3 nm)/Co (8 nm)/Pt (3 nm) shows a ∼ 296% enhancement compared to that of the α-W/Co/Pt system. Meanwhile, a resistivity similar to that of α-W and the spin Hall ratio larger than β-W induce a giant damping-like SOT efficiency per applied electric field, ξ, which is about 12.1 times larger than that of β-W. Our findings will benefit the SOT devices by reducing energy consumption.
自旋轨道扭矩（SOT）效率是自旋电子学的关键问题之一。然而，提高SOT效率通常受到电阻率与自旋霍尔比之间正相关的限制，其中高电阻率往往伴随着大的自旋霍尔比。在此，我们证明亚纳米级β-W插层对α-W（6纳米）/Co（8纳米）/Pt（3纳米）样品的SOT效率有相当大的影响。与α-W/Co/Pt体系相比，α-W（5.7纳米）/β-W（0.3纳米）/Co（8纳米）/Pt（3纳米）的单位电流密度下的类阻尼SOT效率ξ提高了约296%。同时，与α-W相似的电阻率以及大于β-W的自旋霍尔比导致每施加电场的类阻尼SOT效率ξ巨大，约为β-W的12.1倍。我们的发现将通过降低能耗使SOT器件受益。
