Quantum Chirality Dynamics in a Mesoscopic Magnetic Domain Wall

Oleksiy Kolezhuk (Institute of Magnetism, NAS, Ukraine) 

We study the quantum dynamics of the internal chirality degree of freedom of a mesoscopic domain wall pinned inside a quasi-one-dimensional fixture. It is shown that weak spin-polarized current excites 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.

The current density required for the chirality manipulation can be significantly lower compared to the classical regime. We also show that for recently discovered novel class of magnetic materials — altermagnets — chirality switching can be driven by the usual (non-spin-polarized) current.

[1] O. Kolezhuk, R. Teslia, I. Buryak, and O. Gomonay, Phys. Rev. B 109, 134418 (2024)

Contact : R. Ramazashvili