Two-dimensional Site-Bond Percolation as an Example of Self-Averaging System

TL;DR

This study numerically investigates two-dimensional site-bond percolation, demonstrating that it exhibits self-averaging properties consistent with theoretical predictions based on the Harris-Aharony criterion.

Contribution

The paper provides numerical evidence that 2D site-bond percolation exhibits self-averaging, confirming theoretical predictions for models with negative heat exponents.

Findings

The model exhibits self-averaging properties.

Numerical results support the Harris-Aharony criterion.

Self-averaging observed in relative variances R_M and R_χ.

Abstract

The Harris-Aharony criterion for a statistical model predicts, that if a specific heat exponent $\alpha \ge 0$, then this model does not exhibit self-averaging. In two-dimensional percolation model the index $\alpha=-{1/2}$. It means that, in accordance with the Harris-Aharony criterion, the model can exhibit self-averaging properties. We study numerically the relative variances $R_{M}$ and $R_{\chi}$ for the probability $M$ of a site belongin to the "infinite" (maximum) cluster and the mean finite cluster size $\chi$. It was shown, that two-dimensional site-bound percolation on the square lattice, where the bonds play the role of impurity and the sites play the role of the statistical ensemble, over which the averaging is performed, exhibits self-averaging properties.