GAUGE VORTICES ON A SQUARE LATTICE

The effective interaction between gauge vortices on a square lattice i s revealed to be attractive at short distance and oscillate between re pulsion and attraction at long distance. It is analyzed that the stron g attraction at short distance makes the gauge vortices cluster at a g iven flux concentration; while the oscillatory nature in the interacti on potential is the consequence of the existence of the electron Fermi surface in the nonuniform flux phases states.