Hopping conduction mechanism of Pr1−xNdxMnO3 (x=0.3,0.5,0.7)

The temperature dependences of DC electrical resistivity (ρ) of Pr1-xNdxMnO3 (x=0.3, 0.5, 0.7) have been studied in the temperature range from 115K up to 390 K. The samples were prepared by solid state reaction method. In the measured temperature range the resistivity decreases with increasing temperature for all the samples, indicating semiconductor-like behaviour. In the high temperature region, the electrical conduction follows small polaron hopping (SPH) mechanism showing exponential variation of resistivity with temperature. The activation energy decreases with Nd concentration. The low temperature resistivity data follows Mott’s ln(ρT -1/2) ∼ T -1/4 law of VRH conduction mechanism. The estimated values of hopping distances (R) and hopping energies (W) of the samples start to decrease with increasing Nd concentrations. The effect of rare earth site doping on the hopping mechanism have been discussed.