Universal Nonstationary Dynamics at the Depinning Transition

ALEJANDRO B. KOLTON, GRÉGORY SCHEHR, AND PIERRE LE DOUSSAL

PHYSICAL REVIEW LETTERS

American Physical Society

Año: 2009 vol. 103 p. 1606021 - 1606024

0031-9007

We study the nonstationary dynamics of an elastic interface in a disordered medium at the depinning transition. We compute the two-time response and correlation functions, found to be universal and characterized by two independent critical exponents. We find a good agreement between two-loop functional renormalization group calculations and molecular dynamics simulations for the scaling forms, and for the response aging exponent R. We also describe a dynamical dimensional crossover, observed at long times in the relaxation of a finite system. Our results are relevant for the nonsteady driven dynamics of domain walls in ferromagnetic films and contact lines in wetting.