Enhanced magnetoresistance induced collaboratively by spin and orbital currents

Abstract

Orbital currents in light metals or metal oxides without the strong spin–orbit coupling have become an important means to achieve low-power magnetization switching in spin–orbitronic devices. The orbital magnetoresistance (OMR) originated from orbital current represents a useful strategy to explore the interaction between the orbital angular momentum (OAM) and the local magnetic moment. However, systematic research works on the enhancement of OMR and the mechanism of OAM transport are seldom reported. In this study, we report a synergistically enhanced magnetoresistance effect induced by spin and orbital currents in perpendicularly magnetized Pt/Co/Cu–CuOx systems. A maximum room temperature magnetoresistance of 0.38% was observed, exceeding the spin Hall magnetoresistance (SMR) of heavy metal-based heterostructures by one order of magnitude. The enhancement of magnetoresistance is attributed to the contributions from the OMR generated by the orbital Rashba effect at the Cu/CuOx interface and SMR induced by the spin Hall effect in heavy metal Pt. These results provide a pathway to understanding of the OAM transport in magnetic multilayer films and contribute to the design and realization of energy-efficient spin–orbitronic devices.