Universal critical exponents of the magnetic domain wall depinning transition [paper]

PRB Letter 

Universal critical exponents of the magnetic domain wall depinning transition 

L. J. Albornoz, E. E. Ferrero, A. B. Kolton, V. Jeudy, S. Bustingorry, and J. Curiale Phys. Rev. B 104, L060404 – Published 5 August 2021

Magnetic-field-driven domain wall dynamics in a ferrimagnetic GdFeCo thin film with perpendicular magnetic anisotropy is studied using low-temperature magneto-optical Kerr microscopy. Measurements performed in a practically athermal condition allow for the direct experimental determination of the velocity (β=0.30±0.03) and correlation length (ν=1.3±0.3) exponents of the depinning transition. The whole family of exponents characterizing the transition is deduced, providing evidence that the depinning of magnetic domain walls is better described by the quenched Edwards-Wilkinson universality class.

Experimental Results

Domain Wall velocity-field characteristics and avalanche correlation length 

Figure 1 Figure 3

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