Mean-Field Theories for Depinning and their Experimental Signatures
Cathelijne ter Burg, Kay Jörg Wiese
CNRS-Laboratoire de Physique Théorique de
l'Ecole Normale Supérieure, PSL Research University, Sorbonne Universités, UPMC,
24 rue Lhomond, 75005 Paris, France.
Abstract
When driving a disordered elastic manifold through quenched disorder, the
pinning forces exerted on the center of mass are fluctuating, with mean
$f_c=-\overline{F_w} $ and variance $\Delta(w)=\overline{F_w F_0}^c$, where $w$
is the externally imposed control parameter for the preferred position of the
center of mass. $\Delta(w)$ was obtained via the functional renormalization
group in the limit of vanishing temperature $T\to 0$, and vanishing driving
velocity $v\to 0$. There are two fixed points, and deformations thereof, which
are well understood: The depinning fixed point ($T\to 0$ before $v\to 0$)
rounded at $v>0$, and the zero-temperature equilibrium fixed point ($v\to 0$
before $T\to 0$) rounded at $T>0$. Here we consider the whole parameter space
of driving velocity $v>0$ and temperature $T>0$, and quantify numerically the
crossover between these two fixed points.
arXiv:2201.12652 [pdf]
Copyright (C)
by Kay Wiese. Last edited May 10, 2021.