Breakdown of the charge-ordered state in Nd0.5Sr0.5MnO3

It was found that photocurrent or electric-field induced current passing through a Nd0.5Sr0.5MnO, sample in the charge-ordered state could cause a nontransient drop in resistance. It is proposed that a breakdown of the charge-ordered state was induced by current and that metallic filaments are created. This effect largely differs from the electric breakdown or photoinduced transition previously observed in Pr1-xCaxMnO3, 0.3 less than or equal to x less than or equal to 0.5; because no voltage was necessary to sustain the lower resistance state. The effect was reproducible and reversible by annealing the sample at room temperature. [S0163-1829(98)06044-5].