Simultaneous observation of anti-damping and inverse spin Hall effect in La$_{0.67}$Sr$_{0.33}$MnO$_{3}$/Pt bilayer system

Abstract

Manganites have shown potential in spintronics because they exhibit high spin polarization. Here, by ferromagnetic resonance we have studied the damping properties of La0.67Sr0.33MnO3/Pt bilayers which are prepared by oxide molecular beam epitaxy. The damping coefficient (α) of La0.67Sr0.33MnO3 (LSMO) single layer is found to be 0.0104. However the LSMO/Pt bilayers exhibit decrease in α with increase in Pt thickness. This decrease in the value of α is probably due to high anti-damping like torque. Further, we have investigated the angle dependent inverse spin Hall effect (ISHE) to quantify the spin pumping voltage from other spin rectification effects such as anomalous Hall effect and anisotropic magnetoresistance. We have observed high spin pumping voltage (∼ 20 µV ). The results indicate that both anti-damping and spin pumping phenomena are occuring simultaneously. A large value of spin Hall angle of 4.62 has been evaluated.