In-plane ordered grain boundaries inducing enhanced magnetoresistance in epitaxial manganite films

Abstract La 5/8 Ca 3/8 MnO 3 (LCMO) films with [1 1 0]-orientation were epitaxially grown on yttria-stabilized zirconia (1 1 1) [YSZ (1 1 1)] single crystal substrates. The results of X-ray diffractions confirmed that these LCMO/YSZ films show in-plane ordered grain boundaries, which are attributed to the symmetry mismatch between the films and the substrates. It is striking that the films exhibit large magnetoresistance (MR) over a broad temperature range due to the grain boundary effects. The similar feature was observed in polycrystalline manganites. However, it should be noted that our samples are epitaxial in nature. These results indicate that this approach is promising for the fabrication of large area MR devices with controlled grain boundaries.