Spin-orbit torque and spin Hall magnetoresistance in Pt/Co/Ru/AlO x multilayers with modifying spin transport at interfaces

We report the spin-orbit torque and spin Hall magnetoresistance (SMR) in Pt/Co/Ru/AlOx multilayers with modifying spin transport at interfaces. Through current induced magnetization switching and harmonic measurements, we have found that the switching current is decreased and the damping-like effective field is enhanced after inserting Ru layer in Pt/Co/AlOx multilayers. This variation is firstly ascribed to the enhancement of the spin accumulation at the Co/Ru interfaces as discussed in our previous work. Then, the temperature dependence of the SMR in Pt/Co/AlOx and Pt/Co/Ru/AlOx multilayers has been compared. The unexpected temperature dependence of SMR in Pt/Co/Ru/AlOx multilayers is suggested to be the interfacial-generated spin current that transverse into Pt.