Scaling in the Aging Dynamics of the Site-diluted Ising Model

TL;DR

This paper investigates the aging dynamics of the 2D site-diluted Ising model, revealing complex scaling behaviors and fixed points influenced by disorder, with implications for understanding phase-ordering kinetics in disordered systems.

Contribution

It introduces a renormalization-group motivated framework to analyze the phase-ordering kinetics, identifying multiple disorder fixed points and their effects on domain growth.

Findings

Existence of two disorder fixed points with logarithmic and power-law growth.

Rich crossover behavior due to competition between fixed points.

Violation of superuniversality in the scaling behavior.

Abstract

We study numerically the phase-ordering kinetics of the two-dimensional site-diluted Ising model. The data can be interpreted in a framework motivated by renormalization-group concepts. Apart from the usual fixed point of the non-diluted system, there exist two disorder fixed points, characterized by logarithmic and power-law growth of the ordered domains. This structure gives rise to a rich scaling behavior, with an interesting crossover due to the competition between fixed points, and violation of superuniversality.