Monte Carlo Studies of Random Impurity Effects in an Antiferromagnetic Ising Model on the Triangular Lattice

Abstract

Random impurity effects in an antiferromagnetic Ising model with ferromagnetic next nearest neighbor interactions on the triangular lattice are studied by using a Monte Carlo method. It is shown that (i) the ferrimagnetic phase occurring in the pure case is destroyed by a small amount of impurities, whereas (ii) a KT-like phase is not affected much by impurities. A pin effect of impurities is also discussed.