Domain wall motion (DWM) by spin waves (SWs) in different waveforms in a magnetic nanostripe is investigated via micromagnetic simulations. Diversified DWMs are observed. It is found that SW harmonic drives DWM most efficiently and irregular SW may cause abnormal excitation spectrum for DWM in the low-frequency range. We prove that SW harmonic is the basic element when interacting with DW and causes simple creeping motion of DW (i.e. forward propagation of DW accompanied with oscillation) with the same frequency as applied SW harmonic. Under irregular/polychromatic SW, DW makes responses to the energies carried by constituent SW harmonics, instead of overall exhibited torques, and simultaneously conducts multiple creeping motions. This finding enables the analysis for the induced DWM under arbitrary SW. Mapping of SW inside DW reveals that the simple creeping motion is due to real-space expansion and contraction inside DW and the monolithic translation of DW. It is further elucidated that the former relates to the transmitting of spin torques of SW through DW and the latter corresponds to the absorption of spin torques by DW. The overall absorbed spin torques point to direction same as SW propagation and drive DW forward. In addition, the absorption mechanism is evidenced by the well agreement between absorption of SW and averaged velocity of DW. various magnetic structures. In addition, the ability to assist other approaches for improved performance in DWM gives it an extra advantage [50,51].On the other hand, the interplay between SW and DW remains interesting in fundamental physics. Although great effort has been made in understanding the basic characteristics of SW-induced DWM in terms of both theoretical analysis [34,35,[37][38][39]41] and micromagnetic simulations [32-36, 40, 42], the precise picture in dynamics was never determined. So far, two major mechanisms were proposed: magnonic spin-transfer torque (STT) [34] and magnonic linear momentum transfer torque (LMTT) [11,35]. In STT (for a simplified 1D model), linearization on Landau-Lifshitz-Gilbert (LLG) equation gives a solution of reflectionless propagating SW described by a Schrodinger equation. The obtained SW carries a constant magnon current transmitting through DW. Magnons can be viewed as spin-1 bosons with angular momentum ±ÿ and linear momentum ÿk. As a magnon passes through the DW, its spin is changed by 2ÿ; according to the conservation of angular momentum, the spin of 2ÿ must be transferred to DW, which further results in the backward motion of DW with respect to SW propagation [34,41]. On the other hand, what concerns the LMTT theory is the conservation law for linear momentum. LMTT was proposed to explain cases with reflection. Reflected magnon reverses its wave vector k in sign. That is, the linear momentum is changed by 2ÿk. The transfer of linear momentum to DW rewrites the effective field in LLG and causes forward motion of DW [35,42]. STT and LMTT can only be partially correct due to the fact that SW transmission varies with frequenc...

By micromagnetic simulations, we study the current-driven 360° domain wall (360DW) motion in ferromagnetic nanostripe with an in-plane biaxial anisotropy. We observe the critical annihilation current of 360° domain wall can be enhanced through such a type of anisotropy, the reason of which is the suppression of out-of-plane magnetic moments generated simultaneously with domain-wall motion. In details, We have found that the domain-wall width is only related to K y − K x, with K x(y) the anisotropy constant in x(y) direction. Taking domain-wall width into consideration, a prior choice is to keep K y ≈ K x with large enough K. The mode of domain-wall motion has been investigated as well. The traveling-wave-motion region increases with K, while the average DW velocity is almost unchanged. Another noteworthy feature is that a Walker-breakdown-like motion exists before annihilation. In this region, though domain wall moves with an oscillating behavior, the average velocity does not reduce dramatically, but even rise again for a large K.