Current-Induced Reversible Resistance Jumps in La$_{0.8}$Ca$_{0.2}$MnO$_{3}$ Microbridge
Zhang-Yin Zhai1,2,3, Qi-Yun Xie2,4, Gui-Bin Chen1, Xiao-Shan Wu3**, Ju Gao3
1Department of Physics, and Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials, Huaiyin Normal University, Huaian 223300 2Laboratory of Solid State Microstructures, and Department of Physics, Nanjing University, Nanjing 210093 3Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong 4Key Laboratory of Radio Frequency and MicroNano Electronics of Jiangsu Province, Nanjing 210023
Abstract：Two spatially confined La$_{0.8}$Ca$_{0.2}$MnO$_{3}$ (LCMO) microbridges with different widths, starting from a single LCMO film (3 mm$\times$5 mm), 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.
2016, Vol. 33 
