Tunable Charge‐Spin‐Orbital Current Conversion in Light Metals

Angular momentum can be carried by spin and/or orbital degrees of freedom. The light metals such as Nb and V, with tunable thickness, enable the generation of spin currents carrying angular momentum, facilitating the transition from the spin Rashba–Edelstein effect to the spin Hall effect. However, introducing Mn, characterized by large orbital Hall conductivity, allows for controllable angular momentum transport, driving a transition from spin‐based to orbital‐based carriers. Herein, experimental evidence of strong spin Rashba–Edelstein effect is presented at nonmagnetic light‐metal interfaces, revealing through spin‐torque ferromagnetic resonance measurements in Cu/Nb, Cu/V, and Cu/Mn bilayers. This behavior contrasts with that typically observed at conventional heavy‐metal/light‐metal interfaces. In particular, for Cu/Mn system, the Mn thickness dependence of efficiency distinctly demonstrates the angular momentum transport—from being dominated by the spin Rashba–Edelstein effect to the orbital Hall effect. These findings shed light on the fundamental mechanism of the spin Rashba–Edelstein effect and provide a pathway for modulating angular momentum transport.