Journal of Physics C Solid State Physics
Percolation of unfrustrated plaquettes
G. F. Tuthill
Abstract
The author has investigated percolation properties of unfrustrated plaquettes in the two-dimensional Ising model with nearest-neighbour bonds +or-J distributed at random. The effects of plaquette correlations are considered using a two-parameter position-space renormalisation group (PSRG) approach, and it is found (within the framework of this approximate PSRG) that this correlated site percolation problem is in the same universality class as random site percolation. The percolation threshold is then found from large-cell PSRG methods to be indistinguishable from that for randomly placed sites.