Orbital to charge current conversion in copper oxide heterostructures

Abstract: We investigate the orbital-to-charge current conversion in Co${40}$Fe${40}$B$_{20}$\textbar CuO bilayers as a function of CuO thickness, employing orbital pumping via ferromagnetic resonance. The dynamic injection of orbital angular momentum into the CuO layer generates a transverse voltage through the Inverse Orbital Hall Effect (IOHE). By systematically varying the CuO thickness from 2 to 30~nm, we observe a pronounced dependence of the IOHE-induced voltage on the CuO layer thickness, indicating efficient orbital-to-charge conversion. These results highlight the key role of the orbital degree of freedom in orbitronics and provide insights into the potential of transition-metal oxides for next-generation orbitronic devices.