Transport propeties of polycrystalline La_2/3Ca_1/3Mn_1−xCu _xO₃ prepared by Sol-Gel

Abstract

The influence of Cu dopant (x) and sintering temperature (T_s) on the transport properties of La_2/3Ca_1/3Mn_1−xCu_xO₃ series samples prepared by Sol-Gel technique was investigated. X-ray diffraction patterns show that all the samples with different Cu dopant and sintering temperatures (T_s) are of single phase without obvious lattice distortion. Experimental results indicate that the insulator-metal transition temperature is directly related to the sintering temperature and Cu dopant x. It is interesting to observe that a proper amount of Cu dopant can substantially improve magnetoresistance effects.

Keywords

Cu doping / sol-gel / intergrain magnetoresistance

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