Creep via dynamical functional renormalization group

TL;DR

This paper develops a functional renormalization group approach to analyze the creep behavior of a driven interface in a disordered medium, providing a theoretical derivation of the velocity-force characteristics and creep exponent.

Contribution

It introduces finite temperature and velocity FRG equations in a 4-D expansion, enabling a comprehensive study of interface creep in disordered systems.

Findings

Derived FRG equations valid at finite temperature and velocity.

Obtained the form of the v-f characteristics in the creep regime.

Calculated the creep exponent from first principles.

Abstract

We study a D-dimensional interface driven in a disordered medium. We derive finite temperature and velocity functional renormalization group (FRG) equations, valid in a 4-D expansion. These equations allow in principle for a complete study of the the velocity versus applied force characteristics. We focus here on the creep regime at finite temperature and small velocity. We show how our FRG approach gives the form of the v-f characteristics in this regime, and in particular the creep exponent, obtained previously only through phenomenological scaling arguments.