Critical Exponents for the Ferromagnetism in Colossal Magnetoresistance Manganites

Abstract

Critical phenomena of ferromagnetic transition in colossal magnetoresistance manganites are theoretically studied. Concerning the critical exponents for this transition, there still remains controversy among experimental results. In order to clarify intrinsic physics of the manganites through a comparison with theoretical prediction, 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 the mean-field one.