Magnetization-direction-dependent inverse spin Hall effect observed in IrMn/NiFe/Cu/YIG multilayer structure**Project supported by the National Basic Research Program of China (Grant No. 2015CB921502), the National Natural Science Foundation of China (Grant Nos. 11474184 and 11627805), the 111 Project, China (Grant No. B13029), and the Fundamental Research Funds of Shandong University, China.

Abstract

The magnetization-direction-dependent inverse spin Hall effect (ISHE) has been observed in NiFe film during spin Seebeck measurement in IrMn/NiFe/Cu/yttrium iron garnet (YIG) multilayer structure, where the YIG and NiFe layers act as the spin injector and spin current detector, respectively. By using the NiFe/IrMn exchange bias structure, the magnetization direction of YIG (MYIG) can be rotated with respect to that of NiFe (MNiFe) with a small magnetic field, thus allowing us to observe the magnetization-direction-dependent inverse spin Hall effect voltage in NiFe layer. Compared with the situation that polarization direction of spin current (σs) is perpendicular to MNiFe, the spin Seebeck voltage is about 30% larger than that when σs and MNiFe are parallel to each other. This phenomenon may originate from either or both of stronger interface or bulk scattering to spin current when σs and MNiFe are perpendicular to each other. Our work provides a way to control the voltage induced by ISHE in ferromagnets.