In magnetic systems, angular momentum is carried by spin and orbital

degrees of freedom. Nonlocal devices, comprising heavy-metal nanowires on magnetic

insulators like yttrium iron garnet (YIG), enable angular momentum transport via

magnons. These magnons are polarized by spin accumulation at the interface through the

spin Hall effect (SHE) and detected via the inverse SHE (iSHE). The processes are

generally reciprocal, as demonstrated by comparable efficiencies when reversing injector

and detector roles. However, introducing Ru, which enables the orbital Hall effect

(OHE), disrupts this reciprocity. In our system, magnons polarized through combined

SHE and OHE and detected via iSHE are 35% more efficient than the reverse process.

We attribute this nonreciprocity to nonzero spin vorticity, resulting from varying electron

drift velocities across the Pt/Ru interface. This study highlights the potential of orbital

transport mechanisms in influencing angular momentum transport and efficiency in

nonlocal spintronic devices.

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