Curvature-driven ac-assisted creep dynamics of magnetic domain walls

PARIS, F.; GEORGE, J.-M.; DOMENICHINI, P.; GRANADA, M.; KOLTON, A. B.; CAPELUTO, M. G.; PASQUINI, G.

Physical Review B

American Physical Society

Lugar: New York; Año: 2021 vol. 103 p. 1 - 6

2469-9950

The dynamics of micrometer-sized magnetic domains in ultra-thin ferromagnetic films is so dramatically slowed down by quenched disorder that the spontaneous elastic tension collapse becomes unobservable at ambient temperature. By magneto-optical imaging we show that a weak zero-bias AC magnetic field can assist such curvature-driven collapse, making the area of a bubble to reduce at a measurable rate, in spite of the negligible effect that the same curvature has on the average creep motion driven by a comparable DC field. An analytical model explains this phenomenon quantitatively.