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Current-induced phase control in charged-ordered Nd0.5Ca0.5MnO3 and Pr0.6Ca0.4MnO3 crystals

Sachin Parashar·L. Sudheendra·A. R. Raju·C. N. R. Rao
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Abstract

Single crystals of Nd0.5Ca0.5MnO3 and Pr0.6Ca0.4MnO3 show current-induced insulator-metal transitions at low temperatures. In addition, the charge-ordering transition temperature decreases with increasing current. The electroresistive ratio, defined as r0.5/rI where r0.5 is the resistivity at a current of 0.5 mA and rI the resistivity at a given applied current, I, varies markedly with temperature and the value of I. Thermal hysteresis observed in Nd0.5Ca0.5MnO3 and Pr0.6Ca0.4MnO3 at the insulator-metal transition indicates that the transition is first-order. The current-induced changes are comparable to those induced by magnetic fields, and the insulator-metal transition in Pr0.6Ca0.4MnO3 is accordingly associated with a larger drop in resistivity.

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Sachin Parashar, L. Sudheendra, A. R. Raju, C. N. R. Rao. 2003-03-20. Current-induced phase control in charged-ordered Nd0.5Ca0.5MnO3 and Pr0.6Ca0.4MnO3 crystals. https://doi.org/10.1063/1.1641515

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