Reversible steady domain-wall motion driven by a direct current
Phys. Rev. B 114, 154421 – Published 21 September, 2026
DOI: https://doi.org/10.1103/l2f5-6lyv
Abstract
Understanding and manipulating nanoscale domain wall (DW) dynamics is a central topic in magnetism and spintronics for its promising applications in logic and memory devices. In most magnetic systems, inertia affects only transient DW dynamics, while the long-time DW motion is uniquely determined by the magnitude and direction of the applied current. Here we show that this paradigm breaks down in ferrimagnets near the angular momentum compensation point. We demonstrate that a DW can propagate steadily either forward or backward under a direct current, with the direction controlled solely by the current strength. This anomalous phenomenon originates from the inertial dynamics of an internal DW collective coordinate, which behaves as a massive object evolving in a current-dependent double-well potential. By dynamically selecting between distinct stable attractors, inertia qualitatively determines the steady-state response of DWs. The predicted reversal of DW propagation direction is robust against disorders and thermal fluctuations. Our findings establish inertia as a potential control parameter for steady spin dynamics and may provide a novel strategy for controlling magnetic solitons in spintronic systems.
