Velocity-force characteristics of a driven interface in a disordered medium

Abstract

Using a dynamic functional renormalization group treatment of driven elastic interfaces in a disordered medium, we investigate several aspects of the creep-type motion induced by external forces below the depinning threshold $f_c$: i) We show that in the experimentally important regime of forces slightly below $f_c$ the velocity obeys an Arrhenius-type law $v\sim \exp [-U(f)/T]$ with an effective energy barrier $U(f)\propto (f_c-f)$ vanishing linearly when f approaches the threshold $f_c$. ii) Thermal fluctuations soften the pinning landscape at high temperatures. Determining the corresponding velocity-force characteristics at low driving forces for internal dimensions d=1,2 (strings and interfaces) we find a particular non-Arrhenius type creep $v\sim \exp [-(f_c(T)/f{)}^{\mu }]$ involving the reduced threshold force $f_c(T)$ alone. For d=3 we obtain a similar v-f characteristic which is, however, non-universal and depends explicitly on the microscopic cutoff.

9 pages, RevTeX, 3 postscript figures

Cited by in corpus (17)

• Creep and flow regimes of magnetic domain wall motion in ultrathin Pt/Co/Pt films with perpendicular anisotropy
• Universal pinning energy barrier for driven domain walls in thin ferromagnetic films
• Pinning dependent field driven domain wall dynamics and thermal scaling in an ultrathin Pt/Co/Pt magnetic film
• Creep dynamics of elastic manifolds via exact transition pathways
• Creep motion of an elastic string in a random potential
• Depinning and creep motion in glass states of flux lines
• Non-equilibrium relaxation of an elastic string in a random potential
• Growing correlations and aging of an elastic line in a random potential
• Domain Wall Depinning in Random Media by AC Fields
• Creep motion of elastic interfaces driven in a disordered landscape
• Universality of thermally assisted magnetic domain wall motion under spin torque
• Phase transition in site-diluted Josephson junction arrays: A numerical study
• Field theory of disordered systems -- Avalanches of an elastic interface in a random medium
• Marginal pinning of vortices at high temperature
• Thermally rounded depinning of an elastic interface on a washboard potential
• Dynamics of glass phases in the two-dimensional gauge glass model
• Crack propagation by activated avalanches during creep and fatigue from elastic interface theory