More than a decade after the first theoretical and experimental studies of the spin Hall conductivity (SHC) of Pt, both its dominant origin and amplitude remain in dispute. We report the experimental determination of the rapid variation of the intrinsic SHC of Pt with the carrier lifetime (τ) in the dirty-metal regime by incorporating finely dispersed MgO intersite impurities into the Pt, while maintaining its essential band structure. This conclusively validates the theoretical prediction that the SHC in Pt in the dirty-metal regime should be dominated by the intrinsic contribution, and should decrease rapidly with shortening τ. When interfacial spin backflow is taken into account, the intrinsic SHC of Pt in the clean limit is at least 1.6 × 106 (ℏ/2e) ohm−1 m−1, more than 3.5 times greater than the available theoretical predictions. Our work also establishes a compelling spin Hall metal Pt0.6(MgO)0.4 with an internal giant spin Hall ratio of 0.73.
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机译：在对Pt的自旋霍尔电导率（SHC）进行首次理论和实验研究之后的十多年中，其主要起源和振幅仍存在争议。我们报告了通过将细分散的MgO中间杂质掺入Pt，同时保持其必要的能带结构，对Pt固有SHC随载流子寿命（τ）在载金属寿命中快速变化的实验确定。这最终证实了理论预测，即脏金属状态下Pt中的SHC应该由内在贡献控制，并且应随着τ的缩短而迅速降低。考虑到界面自旋回流时，纯净极限中Pt的固有SHC至少为1.6×10 6 （ℏ/ 2e）ohm -1 m -1 ，比可用的理论预测大3.5倍以上。我们的工作还建立了引人注目的自旋霍尔金属Pt0.6（MgO）0.4，内部巨大的自旋霍尔比为0.73。
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