Paper MI+TF-ThA4
Anisotropic Transport in Manganite Films Driven by Selective Tailoring of Emergent Electronic Phase Separation

Thursday, November 12, 2009, 3:00 pm, Room C1

Complex oxides show a wide range of unique behaviors due to their often inseparable energy overlaps of spin-charge-lattice-orbital interactions. These interactions form the basis for emergent electronic phase separation in many complex materials which have been linked to exotic behaviors such as colossal magnetoresistance, the metal-insulator transition, and high T_C superconductivity. By selectively tuning the energetic landscape that shapes the emergent formation of electronic phase separation, we have uncovered never before seen anisotropic transport properties that promise new tunable device applications while answering fundamental questions on the role of electronic phase separation in manganites. Using La_5/8-xPr_xCa_3/8MnO₃ (x = 0.3) (LPCMO) as a model system, we have found that we can selectively induce anisotropic electronic domain formation along one axis of a pseudocubic perovskite single crystal thin film manganite by epitaxially locking it to an orthorhombic substrate. Simultaneous temperature-dependent resistivity measurements along the two perpendicular in-plane axes show significant differences in the metal-insulator transition temperatures and extraordinarily high anisotropic resistivity on macroscales of up to 20000%. These findings show that emergent electronic phase domain formation can be selectively tuned over long distances which opens the door to new device engineering and a fuller understanding of the balanced energetics that drive emergent behaviors in complex materials.