Phase transition in nonmagnetic Al-doped delafossite oxide CuCrO₂: Monte Carlo simulation

In this work, the effects of the lattice defects and random exchange interaction on the phase transition in the classical frustrated spin model (Lin et al., 2014) [14] are investigated by Monte Carlo simulation in order to study the nonmagnetic Al doping effect in CuCrO₂. It is observed that the long range magnetic order can be significantly suppressed by the lattice defects and random exchange induced by the Al substitution, qualitatively consistent with experimental observation. Thus, both the lattice defects and random exchange are confirmed to be responsible for the variation of the transition temperature of CuCr_1−xAl_xO₂ with x. - Highlights: • Al doping effect on phase transition in CuCrO₂ is studied by Monte Carlo simulation of a classical Heisenberg model. • Both the lattice defects and random exchange contribute to the variation of the transition temperature of CuCr_1−xAl_xO₂ with x. • The effect of the lattice defects is proved to be dominant in the Al doping effect in CuCrO₂