Observation Of Magnon-Mediated Electric Current Drag At Room Temperature

Spin-based electronic devices such as magnetic memory and spin logic rely on spin information transport. Conduction electrons, due to their intrinsic spin angular momentum, become an obvious choice for spin information carriers. Here, we experimentally demonstrate that magnons, quasiparticles representing low-energy excitations of ferromagnetic materials, can serve as effective spin information carriers as well. Specifically, we consider two nonmagnetic heavy metals (HMs) that are separated by an electric leak-free ferrimagnetic insulator. When an electric current is applied in one of the HM layers, magnons in the ferrimagnetic insulator are excited and become an effective medium to couple the spin currents in two HMs. As a result, the charge/spin current in one HM layer can drag a charge/spin current in the other HM layer. This work provides a route for spin-based electronic devices where the spin transport is carried by quasiparticles other than electrons.