Electronic transport properties of La_2/3Ca_1/3Mn_0.98Cu_0.02O₃ sintered at different temperature

Abstract

The sol-gel method was adopted to prepare series of La_2/3Ca_1/3Mn_0.98Cu_0.02O₃ samples sintered at different temperatures, and the structure of samples, high-temperature electrical conductive mechanism and electronic transport properties of double-peak resistance were investigated. X-ray diffraction pattern indicates that the samples are in perovskite structures and obey the Variable-Rang Hopping Mechanism of ρ=ρ ₀exp[(T ₀/T)^1/4] under high temperatures during the electrical conduction. In addition, based on the polycrystalline granular system surface and image, the reasonable explanation was given for the double-peak resistance phemomenon.

Keywords

sol-gel / Cu doping / electrical conductive mechanism / rare earth

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