Curvature-driven ac-assisted creep dynamics of magnetic domain walls [paper]

 PRB Letter

 

P. Domenichini, F. Paris, M. G. Capeluto, M. Granada, J.-M. George, G. Pasquini, and A. B. Kolton Phys. Rev. B 103, L220409 – Published 24 June 2021

The dynamics of micrometer-sized magnetic domains in ultrathin 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.

Experiment

Figure 1

Interactive Simulation of a time dependent phi4 model

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