We theoretically study the dynamics of ferrimagnetic domain walls in the presence of Dzyaloshinskii-Moriya interaction. We find that an application of a DC magnetic field can induce terahertz spin-wave emission by driving ferrimagnetic domain walls, which is not possible for ferromagnetic or antiferromagnetic domain walls. Dzyaloshinskii-Moriya interaction is shown to facilitate the teraherz spin-wave emission in wide ranges of net angular momentum by increasing the Walkerbreakdown field. Moreover, we show that spin-orbit torque combined with Dzyaloshinskii-Moriya interaction also drives a fast ferrimagnetic domain wall motion with emitting terahertz spin-waves in wide ranges of net angular momentum.
@article{arxiv.1706.00549,
title = {Coherent Terahertz Spin-Wave Emission Associated with Ferrimagnetic Domain Wall Dynamics},
author = {Se-Hyeok Oh and Se Kwon Kim and Dong-Kyu Lee and Gyungchoon Go and Kab-Jin Kim and Teruo Ono and Yaroslav Tserkovnyak and Kyung-Jin Lee},
journal= {arXiv preprint arXiv:1706.00549},
year = {2017}
}