Spin-orbit torques in laminated tungsten multilayers with nominally doped oxygen

Spin-orbit torques in laminated tungsten multilayers with nominally doped oxygen

Physical Review Applied

10.1103/PhysRevApplied.23.014009

https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.23.014009

James Lourembam, Hong Jing Chung, Lisen Huang, Khoong Hong Khoo, Jinjun Qiu, Huiqing Xie, D.V. Maheswar Repaka, Sherry Lee Koon Yap, Hang Khume Tan, BingJin Chen, Seng Kai Wong, Abhijit Ghosh, Haidong Liang, Sabpreet Bhatti, T.S. Suraj, Andrew Anthony Bettiol, Anjan Soumyanarayanan, S.N. Piramanayagam, Sze Ter Lim

General Materials Science

06 January 2025

Lourembam, J., Chung, H. J., Huang, L., Khoo, K. H., Qiu, J., Xie, H., Repaka, D. V. M., Yap, S. L. K., Tan, H. K., Chen, B., Wong, S. K., Ghosh, A., Liang, H., Bhatti, S., Suraj, T. S., Bettiol, A. A., Soumyanarayanan, A., Piramanayagam, S. N., & Lim, S. T. (2025). Spin-orbit torques in laminated tungsten multilayers with nominally doped oxygen. Physical Review Applied, 23(1), 014009. https://doi.org/10.1103/PhysRevApplied.23.014009

Spin-orbit torque (SOT) control of magnetization is being rapidly positioned for energy-efficient computing across various memory hierarchies. Concurrently, the study of intrinsic and extrinsic factors, such as doping, to enhance SOT is of considerable scientific interest. Here, we introduce 2% nominally doped oxygen via postdeposition oxygen flow in β-phase tungsten, one of the most promising SOT materials, to create laminated [W/O] structures. Incorporating them into annealed multilayer stacks compatible with industrial production, we find ∼50% enhancement in spin-Hall angle with minimal compromise in intrinsic spin-Hall conductivity. Furthermore, we integrate [W/O] into SOT magnetic tunnel junctions, achieving ∼30% reduction in critical switching current densities while maintaining a relatively large tunnel magnetoresistance (>135%). Our findings highlight that engineering nominal doping in established SOT materials offers an attractive alternative for accelerating materials development for SOT magnetic random-access memory (MRAM).

Publisher Copyright

This research / project is supported by the Agency for Science, Technology and Research (A*STAR) - RIE 2020 - SpOT-LITE programme
Grant Reference no. : A18A6b0057

https://oar.a-star.edu.sg/communities-collections/articles/21443

2331-7019

Institute of Materials Research and Engineering