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arXiv · 1811.10329

Universal dimensional crossover of domain wall dynamics in ferromagnetic films

W. Savero Torres·R. Diaz Pardo·S. Bustingorry·A. B. Kolton·A. Lemaître·V. Jeudy
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Abstract

The magnetic domain wall motion driven by a magnetic field is studied in (Ga,Mn)As and (Ga,Mn)(As,P) films of different thicknesses. In the thermally activated creep regime, a kink in the velocity curves and a jump of the roughness exponent evidence a dimensional crossover in the domain wall dynamics. The measured values of the roughness exponent zeta_{1d} = 0.62 +/- 0.02 and zeta_{2d} = 0.45 +/- 0.04 are compatible with theoretical predictions for the motion of elastic line (d = 1) and surface (d = 2) in two and three dimensional media, respectively.

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W. Savero Torres, R. Diaz Pardo, S. Bustingorry, A. B. Kolton, A. Lemaître, V. Jeudy. 2018-11-26. Universal dimensional crossover of domain wall dynamics in ferromagnetic films. https://doi.org/10.1103/physrevb.99.201201

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