Random-manifold to random-periodic depinning of an elastic interface

BUSTINGORRY SEBASTIAN; KOLTON ALEJANDRO B.; GIAMARCHI THIERRY

PHYSICAL REVIEW B

AMER PHYSICAL SOC

Año: 2010 vol. 82 p. 94202 - 94219

1098-0121

We study numerically the depinning transition of driven elastic interfaces in a random-periodic medium with localized periodic-correlation peaks in the direction of motion. The analysis of the moving interface geometry reveals the existence of several characteristic lengths separating different length-scale regimes of roughness. We determine the scaling behavior of these lengths as a function of the velocity, temperature, driving force, and transverse periodicity. A dynamical roughness diagram is thus obtained which contains, at small length scales, the critical and fast-flow regimes typical of the random-manifold or domain wall depinning, and at large length scales, the critical and fast-flow regimes typical of the random-periodic or charge-density wave depinning. From the study of the equilibrium geometry we are also able to infer the roughness diagram in the creep regime, extending the depinning roughness diagram below threshold. Our results are relevant for understanding the geometry at depinning of arrays of elastically coupled thin manifolds in a disordered medium such as driven particle chains or vortex-line planar arrays. They also allow to properly control the effect of transverse periodic boundary conditions in large-scale simulations of driven disordered interfaces.