Current-controlled chirality dynamics in a mesoscopic magnetic domain wall

Abstract

Chirality as internal degree of freedom of a mesoscopic domain wall inside a quasi-one-dimensional fixture can be controlled by spin-polarized current for ferro- as well as anti-ferro-magnetic domain walls. We show that the current density required for the chirality manipulation can be significantly reduced in the low-temperature regime where the chirality dynamics exhibits quantum effects. In this quantum regime, weak currents can excite Bloch oscillations of the domain wall angular rotation velocity, with the oscillation frequency proportional to the current, modulated by a much higher magnon-range frequency. In addition to that, the Wannier-Stark localization effects enable controlled switching between different chiral states, suppressing inertial effects characteristic for the classical regime. We also show that for recently discovered novel class of magnetic materials -- altermagnets -- chirality switching can be driven by the usual charge current (not spin-polarized).