Current-induced metastable resistive state in epitaxial thin films of La1−xCaxMnO3 (x=0.2, 0.3)

The influence of a transport dc current on electric resistivity has been investigated in epitaxial thin films of La1−xCaxMnO3 (x=0.2, 0.3). A most prominent finding is the appearance of a remarkable resistive peak at temperatures well below the Curie temperature Tc. Such a resistive peak is developed when the dc current over a critical value was applied in a temperature cycling from 300 to 10 K. The resistance peak turns out to be extremely sensitive to a weak current. Even a very small current could greatly depress the height of the peak. Such a current-induced state with high resistivity is metastable compared to the pristine state. The stability of the induced state has been also studied.