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

Abstract

The rapidly evolving utilization of spin Hall effect (SHE) arising from spin-orbit coupling in $5d$ transition metals and alloys has made giant strides in the development of designing low-power, robust, and nonvolatile magnetic memory. Recent studies, on incorporating nonmetallic lighter elements such as oxygen, nitrogen, and sulfur into $5d$ transition metals, have shown an enhancement in dampinglike torque efficiency ${\ensuremath{\theta}}_{\mathrm{DL}}$ due to the modified SHE, but the mechanism behind this enhancement is not clear. In this paper, we study ${\ensuremath{\theta}}_{\mathrm{DL}}$ at different temperatures (100--293 K) to disentangle the intrinsic and extrinsic side-jump scattering induced SHE in N-implanted Pt. We observe a crossover of intrinsic to extrinsic side-jump mechanism as the implantation dose increases from $2\ifmmode\times\else\texttimes\fi{}{10}^{16}$ to $1\ifmmode\times\else\texttimes\fi{}{10}^{17}\phantom{\rule{0.16em}{0ex}}\mathrm{ions}/\mathrm{c}{\mathrm{m}}^{2}$. A sudden decrease in the intrinsic spin Hall conductivity is counterbalanced by the increase in the extrinsic side-jump induced SHE efficiency. These results conclude that studying ${\ensuremath{\theta}}_{\mathrm{DL}}$ as a function of implantation dose, and as a function of temperature, is important to understand the physical mechanism contributing to SHE.