CORRELATED SITE-BOND PERCOLATION ON A SQUARE LATTICE

A percolation model is studied, on a square lattice, with computer sim ulations. The sites and bonds distributions overlap and introduce corr elations between sites and bonds, The percolation thresholds have been evaluated numerically. Percolation becomes easier as the correlation increases. The percolation probability (i.e. the percolating cluster m ass) shows a change in its behaviour as the correlation changes, For l ow correlation it grows monotonically but for large correlations it sh ows a maximum. Similar characteristics have previously been found on a Bethe lattice.