Abstract
Using a two-orbital model and Monte Carlo simulations, we investigate the effect of nonmagnetic B-site
substitution on half-doped CE-type manganites. The lattice defects induced by this substitution destabilize the
CE phase, which transforms into 1 the ferromagnetic FM metallic competing state, 2 a regime with
short-range FM clusters, or 3 a spin-glass state, depending on couplings and on the valence of the B-site
substitution. While a C-type antiferromagnetic state is usually associated with an average eg charge density of
less than 0.5, the nonmagnetic B-site substitution that lowers the eg charge density is still found to enhance the
FM tendency in our simulations. The present calculations are in qualitative agreement with experiments and
provide a rationalization for the complex role of nonmagnetic B-site substitution in modulating the phase
transitions in manganites.
