Electrical manipulation of spin pumping signal through nonlocal thermal magnon transport

Abstract

We study the magnon transport in the nonlocal configuration composed of two Pt strips on top of a yttrium iron garnet, with and without the presence of RF microwaves generated by an on-chip antenna. We find that the spin-Hall induced thermal magnon heating/cooling, the Oersted field, and the Joule heating generated by the alternating current in the Pt injector can significantly influence the spin-pumping signal measured by the Pt detector in the presence of RF microwaves, forcing the spin-pumping voltage to show up in the first and second harmonic signals in the nonlocal magnon transport measurement. These results indicate that the nonlocal magnon transport configuration can serve as a structure to electrically detect and manipulate the spin-pumping signal. Furthermore, certain caution is needed when studying the interplay between incoherent magnon and coherent magnon spin transport in the nonlocal transport configuration, since the change in microwave-induced spin-pumping voltage can overwhelm the incoherent magnon transport signals.