Effect of nonmagnetic impurities (Zn, Li) in a hole-doped spin-fermion model for cuprates

The effect of adding nonmagnetic impurities (NMI's), such as Zn or Li, to high-ir, cuprates is studied applying Monte Carlo techniques to a spin-fermion model. It is observed that adding Li is qualitatively similar to doping with equal percentages of Sr and Zn. The mobile holes (MH) are trapped by the NMI and the system remains insulating and commensurate with antiferromagnetic (AF) correlations. This behavior persists in the region %NMI> % MH. On the other hand, when %NMI