Monopole percolation in the compact Abelian Higgs model

We have studied the monopole-percolation phenomenon in the four dimensional Abelian theory that contains compact U(1) gauge fields coupled to unitary norm Higgs fields. We have determined the location of the percolation transition line in the plane (Formula presented) This line overlaps the confined-Coulomb and the confined-Higgs phase transition lines, originated by a monopole-condensation mechanism, but continues away from the end point where this phase transition line stops. In addition, we have determined the critical exponents of the monopole percolation transition away from the phase transition lines. We have performed the finite size scaling in terms of the monopole density instead of the coupling, because the density seems to be the natural parameter when dealing with percolation phenomena. © 1998 The American Physical Society.