We experimentally investigate the origin of two-magnon scattering (TMS) in heavy-metal (HM)/ferromagnet (FM)/oxide heterostructures (FM = $\mathrm{Co}$, ${\mathrm{Ni}}_{81}{\mathrm{Fe}}_{19}$, or ${\mathrm{Fe}}_{60}{\mathrm{Co}}_{20}{\mathrm{B}}_{20}$) by varying the materials located above and below the FM layer. We show that strong TMS in HM/FM/oxide systems arises primarily at the HM/FM interface and increases with the strength of the interfacial spin-orbit coupling and magnetic roughness at this interface. TMS at the FM/oxide interface is relatively weak, even in systems where spin-orbit coupling at this interface generates strong interfacial magnetic anisotropy. We also suggest that the spin-current-induced excitation of nonuniform short-wavelength magnons at the HM/FM interface may function as a mechanism of spin memory loss for the spin-orbit torque exerted on the uniform mode.

中文翻译：

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重金属/铁磁体/氧化物异质结构中强两磁子散射的起源

我们通过实验研究了重金属（HM）/铁磁体（FM）/氧化物异质结构（FM = $\mathrm{有限公司}$， ${你}_{81}{铁}_{19}$， 要么 ${铁}_{60}{\mathrm{有限公司}}_{20}{\mathrm{乙}}_{20}$），方法是更改​​位于FM层上方和下方的材料。我们表明，强HM / FM /氧化物系统中的强TMS主要出现在HM / FM界面处，并随着界面自旋轨道耦合强度和该界面处的磁粗糙度而增加。FM /氧化物界面处的TMS相对较弱，即使在该界面处的自旋-轨道耦合产生强界面磁各向异性的系统中也是如此。我们还建议，自旋电流在HM / FM界面处引起的非均匀短波磁振子的激发可能起自旋记忆损失的作用，该自旋记忆损失是由于施加在均匀模式上的自旋轨道转矩引起的。