Universal dimensional crossover of domain wall dynamics in ferromagnetic films

W. Savero Torres (1) , R Díaz Pardo (1) , S. Bustingorry (2) , A. Kolton (2) , Aristide Lemaitre (3) , Vincent Jeudy (1)

1 LPS - Laboratoire de Physique des Solides
2 Centro Atómico Bariloche [Argentine]
3 C2N (UMR_9001) - Centre de Nanosciences et Nanotechnologies

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 ζ 1d = 0.62 ± 0.02 and ζ 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.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

W. Savero Torres, R Díaz Pardo, S. Bustingorry, A. Kolton, Aristide Lemaitre, et al.. Universal dimensional crossover of domain wall dynamics in ferromagnetic films. Physical Review B, 2019, 99 (20), ⟨10.1103/PhysRevB.99.201201⟩. ⟨hal-02352304⟩