Micromagnetic Investigation of a Voltage-Controlled Skyrmionic Magnon Switch

This work proposes and numerically studies a skyrmionic-magnon-switch (SMS) device, where a Néel-type skyrmion acts as a programmable scattering center to route propagating spin waves. Our results show that the effective deflection of magnons by a skyrmion strongly depends on the ratio of magnon wavelength to skyrmion diameter, which is as large as 30° when the skyrmion diameter is comparable to the magnon wavelength. This offers the possibility to program the routing of magnons in a network of ferromagnetic wires, by controlling the perpendicular magnetic anisotropy of the ferromagnetic film via the voltage-controlled magnetic anisotropy effect, which, in turn, controls the skyrmion size, stability, and spin-wave deflection angle. The proposed SMS device allows for electrical routing of spin waves between branches of a magnonic circuit, a functionality that is fundamental to emerging magnonic logic and computing concepts. It is shown that on:off ratios as large as 90× are achievable in such an SMS device using realistic material parameters.