Critical exponents for the ferromagnetism in colossal magnetoresistance manganites

Critical phenomena of the ferromagnetic transition in colossal magnetoresistance manganites are theoretically studied. Concerning the critical exponents for this transition, there still remains controversy among the experimental results. In order to clarify the intrinsic physics of the manganites through a comparison with theoretical predictions, we investigate the critical phenomena of double-exchange models by using finite-size scaling analysis on unbiased numerical results. As a result, we show that the critical exponents of the ferromagnetic transition of the three-dimensional double-exchange model is consistent with those of the Heisenberg model, but are distinct from those of the mean-field one. (orig.)