Spin-wave-driven skyrmion dynamics in ferrimagnets: Effect of net angular momentum

Abstract

Searching for low-power-consuming and highly efficient methods for well-controllable driving of skyrmion motion is one of the most concerning issues for future spintronic applications, raising high concern with the choice of magnetic media and driving scenario. In this work, we propose a scenario of spin-wave-driven skyrmion motion in a ferrimagnetic (FiM) lattice with the net angular momentum ${\ensuremath{\delta}}_{s}$. We investigate theoretically the effect of both ${\ensuremath{\delta}}_{s}$ and the circular polarization of the spin wave on the skyrmion dynamics. It is revealed that the momentum onto the skyrmion imposed by the excited spin wave can be partitioned into a ferromagnetic term plus an antiferromagnetic term. The ratio of these two terms and consequently the Hall angle of skyrmion motion can be formulated as the functions of ${\ensuremath{\delta}}_{s}$, demonstrating the key role of ${\ensuremath{\delta}}_{s}$ as an effective control parameter for the skyrmion motion. Moreover, the spin wave frequency and chirality dependent skyrmion motion are discussed, predicting the frequency enhanced skyrmion Hall motion. This work thus represents an essential contribution to understanding the skyrmion dynamics in a FiM lattice.