Enhanced Spin Hall Effect in S‐Implanted Pt. Issue 1 (3rd December 2020) - Shashank, Utkarsh
Abstract: High efficiency of charge–spin interconversion in spin Hall materials is a prime necessity to apprehend intriguing functionalities of spin–orbit torque for magnetization switching, auto‐oscillations, and domain wall motion in energy‐efficient and high‐speed spintronic devices. To this end, innovations in fabricating advanced materials that possess not only large charge–spin conversion efficiency but also viable electrical and spin Hall conductivity are of importance. Here, a new spin Hall material designed by implanting low energy 12 keV sulfur ions in heavy metal Pt, named as Pt(S), is reported that demonstrates eight times higher conversion efficiency as compared to pristine Pt. The figure of merit, spin Hall angle ( θ SH ), up to θ SH Pt ( S ) of 0.502 together with considerable electrical conductivity σ xx Pt ( S ) of 1.65 × 10 6 Ω –1 m –1 is achieved. The spin Hall conductivity σ SH Pt ( S ) increases with increasing σ xx Pt ( S ), as σ SH Pt ( S ) ∝ σ xx Pt ( S ) 1.7, implying an intrinsic mechanism in a dirty metal conduction regime. A comparatively large σ SH Pt ( S ) of 8.32 × 10 5 ( ℏ 2 e ) Ω –1 m –1 among the reported heavy‐metals‐based alloys can be useful for developing next‐generation spintronic devices using spin–orbit torque. Abstract : The present work proposes a new spin Hall material, Pt(S), designed by 12 keV sulfur (S)‐ion implantation in platinum (Pt), which demonstrates eight times (three times) enhanced charge‐to‐spin interconversion efficiency at 10 K (300 K). Furthermore, its large spin Hall conductivity of ≈8.32 × 10 5 ( ℏ 2 e ) Ω –1 m –1 among the reported pure Pt and other derivative alloys dictates the suitability of Pt(S) for next‐generation spin–orbit‐torque‐driven logic and memory device applications.