Resistivity Minimum Behavior and Weak Magnetic Disorder Characteristics in La2/3Ca1/3MnO3 Manganites

The correlation of low temperature resistivity minimum with magnetic properties was studied by a tuned action in applied magnetic fields for the optimal doping La2/3Ca1/3MnO3 manganite. It is proved that the low temperature minimum results from the existence of intrinsic spin disorder with a weak magnetic disorder characteristic caused from antiferromagnetism background and ferromagnetic ground state. The best fittings were made for the high field, accompanied by disappearing of Kondo term; the electronic resistivity follows only T1/2 dependence with a characteristic of enhanced e-e interactions and carrier localization. This e-e interaction at low and high fields would be a general characteristic and it reflects the strong correlated interaction between electrons in mixed-valent manganites.