Current-Induced Reversible Resistance Jumps in La_0.8Ca_0.2MnO₃ Microbridge

【摘要】 Two spatially confined La_0.8Ca_0.2MnO₃（LCMO） microbridges with different widths,starting from a single LCMO film（3mmx5mm）,are fabricated by optical lithography.A second new and robust metal-insulator transition（MIT） peak at about 75 K appears,in addition to the normal MIT at 180 K observed in the standard LCMO film.When the two bridges are processed by currents of high densities,interesting reversible resistance jumps are excited only around the new peak.A stronger dependence of resistance jump on current excitation is found for the bridge with a smaller width.The temperature driven transition between new excited multiple metastable states are involved to explain the interesting low-temperature ultra-sharp jumps.更多还原

【Abstract】 Two spatially confined La_0.8Ca_0.2MnO₃（LCMO） microbridges with different widths,starting from a single LCMO film（3mmx5mm）,are fabricated by optical lithography.A second new and robust metal-insulator transition（MIT） peak at about 75 K appears,in addition to the normal MIT at 180 K observed in the standard LCMO film.When the two bridges are processed by currents of high densities,interesting reversible resistance jumps are excited only around the new peak.A stronger dependence of resistance jump on current excitation is found for the bridge with a smaller width.The temperature driven transition between new excited multiple metastable states are involved to explain the interesting low-temperature ultra-sharp jumps.更多还原