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arXiv · 2211.03355

Disentanglement of intrinsic and extrinsic side-jump scattering induced spin Hall effect in N-implanted Pt

Utkarsh Shashank·Yoji Nakamura·Yu Kusaba·Takafumi Tomoda·Razia Nongjai·Asokan Kandasami·Rohit Medwal·Rajdeep Singh Rawat·Hironori Asada·Surbhi Gupta·Yasuhiro Fukuma
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Abstract

The rapidly evolving utilization of spin Hall effect (SHE) arising from spin-orbit coupling in 5d transition metals and alloys have made giant strides in the development of designing low-power, robust and non-volatile magnetic memory. Recent studies, on incorporating non-metallic lighter elements such as oxygen, nitrogen and sulfur into 5d transition metals, have shown an enhancement in damping-like torque efficiency {\theta}_DL due to the modified SHE, but the mechanism behind this enhancement is not clear. In this paper, we study {\theta}_DL at different temperatures (100-293 K) to disentangle the intrinsic and extrinsic side-jump scattering induced spin Hall effect in N-implanted Pt. We observe a crossover of intrinsic to extrinsic side-jump mechanism as the implantation dose increases from 2*10^16 ions/cm2 to 1*10^17 ions/cm2. A sudden decrease in the intrinsic spin Hall conductivity is counterbalanced by the increase in the side-jump induced SHE efficiency. These results conclude that studying {\theta}_DL as a function of implantation dose, and also as a function of temperature, is important to understand the physical mechanism contributing to SHE, which has so far been unexplored in incorporating non-metallic element in 5d transition metals.

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Utkarsh Shashank, Yoji Nakamura, Yu Kusaba, Takafumi Tomoda, Razia Nongjai, Asokan Kandasami, Rohit Medwal, Rajdeep Singh Rawat, Hironori Asada, Surbhi Gupta, Yasuhiro Fukuma. 2022-11-07. Disentanglement of intrinsic and extrinsic side-jump scattering induced spin Hall effect in N-implanted Pt. https://doi.org/10.1103/physrevb.107.064402

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