Current-voltage (I-V) characteristics of Pr_(0.5)Sr_(0.3)Ca_(0.2)MnO_(3) are measured at different temperatures and different fields. Our data of I-V curves show a crossover from linear to nonlinear behavior at the temperature lower than the charge ordering temperature. New findings in this work include (i) abrupt jumps/drops of voltage in each I-V curve below 100 K and (ii) an enhancement of magnetoresistance (MR) ratio from 15 to 20 which is associated with the unusual voltage jumps/drops in I-V curves. The enhancement of MR ratio evidences the existence of an intermediate state between the charge ordering state and the charge ordering breakdown state. Most importantly, the existence of such intermediate state provides a new route to achieve a low field colossal magnetoresistance for future applications of spintronics.
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