Large Spin Anomalous Hall Effect in L1$\rm_{0}$-FePt: Symmetry and Magnetization Switching

We quantitatively evaluate a spin anomalous Hall effect (SAHE), generating spin angular momentum flow (spin current, $J_{\rm s}$), in an L1$\rm_{0}$-FePt ferromagnet by exploiting giant magnetoresistance devices with L1$\rm_{0}$-FePt / Cu / Ni$\rm_{81}$Fe$\rm_{19}$ . From the ferromagnetic resonance linewidth modulated by the charge current ($J_{\rm c}$) injection, the spin anomalous Hall angle ($\alpha_{\rm SAH}$) is obtained to be 0.25 $\pm$ 0.03. The evaluation of $\alpha_{\rm SAH}$ at different configurations between $J_{\rm c}$ and magnetization enables us to discuss the symmetry of SAHE and gives the unambiguous evidence that SAHE is the source of $J_{\rm s}$. Thanks to the large $\alpha_{\rm SAH}$, we demonstrate the SAHE-induced magnetization switching.