Presentation Information
[15p-K303-1]Study of Metal, Oxide, and Hybrid Metal-Oxide Interlayers for optimizing Spin-Orbit torque in BiSb Topological Insulator and Magnetic Interfaces
〇(D)Ruixian Zhang1, Quang Le2, Xiaoyong Liu2, Lei Xu2, Brian R. York1, Cherngye Hwang1, Son Le2, Maki Maeda3, Fan Tuo3, Hisashi Takano3, Min Liu1, Shota Namba1, Pham Nam Hai1 (1.Tokyo Sci., 2.WD, Great Oaks site, 3.WD, Fujisawa site)
Keywords:
topological insulator,interfacial effect,Spin Hall effect
In this work, we have investigated and compared the effects of inserting metal, oxide, and hybrid metal-oxide interlayers such as NiFeGe, MgO, NiFeGe/MgO, and NiFeGe/MgTiO, respectively, in between the 10 nm BiSb layer and ferromagnetic (FM) [0.8 nm Co40Fe60] layer that was deposited at room temperature on a silicon oxide substrate.
Both NiFeGe and MgO improve Spin Hall angle (SHA) of BiSb comparing with that of BiSb with no interlayer. Since both NiFeGe and MgO can prevent unwanted interaction between the FM and TI, they can protect the BiSb topological surface states and result in improved intrinsic SHA. Meanwhile, the hybrid NiFeGe (9 Å)/ MgO (3 Å) interlayers shows the highest SHA.
Our study provides a useful framework for understanding ultrahigh charge-to-spin conversion efficiencyand guidance on increasing it by optimizing the interlayer material for ultralow power SOT applications.
Both NiFeGe and MgO improve Spin Hall angle (SHA) of BiSb comparing with that of BiSb with no interlayer. Since both NiFeGe and MgO can prevent unwanted interaction between the FM and TI, they can protect the BiSb topological surface states and result in improved intrinsic SHA. Meanwhile, the hybrid NiFeGe (9 Å)/ MgO (3 Å) interlayers shows the highest SHA.
Our study provides a useful framework for understanding ultrahigh charge-to-spin conversion efficiencyand guidance on increasing it by optimizing the interlayer material for ultralow power SOT applications.
Comment
To browse or post comments, you must log in.Log in