Evidence for phonon skew scattering in the spin Hall effect of Pt was presented in a recent experimental-theoretical study of a multilayer of Pt|Co|AlO_x by G. V. Karnad, et al., Phys. Rev. B 97, 100405(R) (2018). The observed, strikingly nonmonotonic temperature dependence of the spin Hall angle is compatible with theoretical predictions which include both intrinsic and extrinsic (impurities and phonons) contributions.

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