Effects of Anisotropic Strain on Spin-Orbit Torque Produced by the Dirac Nodal Line Semimetal IrO2

被引：44

作者：

Bose, Arnab ^{[2
]}

Nelson, Jocienne N. ^{[1
]}

Zhang, Xiyue S. ^{[2
]}

Jadaun, Priyamvada ^{[3
]}

Jain, Rakshit ^{[1
]}

Schlom, Darrell G. ^{[4
,5
]}

Ralph, Daniel C. ^{[1
,5
]}

Muller, David A. ^{[2
,5
]}

Shen, Kyle M. ^{[1
,5
]}

Buhrman, Robert A. ^{[2
]}

机构：

[1] Cornell Univ, Dept Phys, Ithaca, NY 14853 USA

[2] Cornell Univ, Sch Appl & Engn Phys, Ithaca, NY 14853 USA

[3] Univ Texas Austin, Dept Elect & Comp Engn, Austin, TX 78712 USA

[4] Cornell Univ, Dept Mat Sci & Engn, Ithaca, NY 14853 USA

[5] Kavli Inst Cornell Nanoscale Sci, Ithaca, NY 14853 USA

来源：

ACS APPLIED MATERIALS & INTERFACES | 2020年 / 12卷 / 49期

基金：

美国国家科学基金会;

关键词：

complex oxide heterostructures; spin-orbit-torques; Dirac nodal line (DNL); crystal symmetry; strain and band topology; amsotropic spin Hall conductivity; spin-torque ferromagnetic resonance (ST-FMR);

D O I：

10.1021/acsami.0c16485

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

We report spin-torque ferromagnetic resonance studies of the efficiency of the damping-like (xi(DL)) spin-orbit torque exerted on an adjacent ferromagnet film by current flowing in epitaxial (001) and (110) IrO2 thin films. IrO2 possesses Dirac nodal lines (DNLs) in the band structure that are gapped by spin- orbit coupling, which could enable a very high spin Hall conductivity, sigma(SH). We find that the (001) films do exhibit exceptionally high xi(DL) ranging from 0.45 at 293 K to 0.65 at 30 K, which sets the lower bounds of sigma(SH) to be 1.9 x 10(5 )and 3.75 x 10(5) Omega(-1) m(-1), respectively, 10 times higher and of opposite sign than the theoretical prediction. Furthermore, xi(DL) and sigma(SH) are substantially reduced in anisotropically strained (110) films. We suggest that this high sensitivity to anisotropic strain is because of changes in contributions to sigma(SH) near the DNLs.

引用

页码：55411 / 55416

页数：6

共 33 条

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