Current tunable electroresistance and magnetothermal cooling with a phase separated manganite

We investigate the effect of dc current on the field dependence of the magnetoresistance in the phase separated manganites Nd$_{0.5}$Ca$_{0.5}$Mn$_{0.93}$Ni$_{0.07}$O$_{3. }$ We show that temperature of the sample in presence of a magnetic field (H) and dc current (I = 20 mA) decreases abruptly as much as $\Delta $T = 45 K (7 K) accompanied by a step like decrease in the magnetoresistance at a critical value of H when the base temperature is 40 K (100 K). The magnitude of $\Delta $T and the position of magnetoresistance step decrease towards lower H with decreasing amplitude of the current. In addition, the applied current significantly modifies the irreversible behavior of magnetoresistance observed at lower currents (I $<$ 1 mA). We discuss possible origins of the current and magnetic -field driven temperature change which may find applications in magnetothermal refrigeration besides magnetocaloric effect.