The electronic and magnetic properties of La0.85Zr0.15MnO3 deposited on SrTiO3 and MgO substrates.

The electronic and magnetic properties of tetravalent-ion-doped La_0.85Zr_0.15MnO₃ (LZMO) thin films that were epitaxially grown on SrTiO₃ (STO) and MgO substrates were studied using temperature-dependent x-ray diffraction (XRD), x-ray absorption near-edge structure, x-ray linear dichroism, and x-ray magnetic circular dichroism at the Mn L_3,2- and K-edge. XRD studies reveal that the LZMO thin films have compressive and tensile strains (along the c-axis) on the STO and MgO substrates, respectively. As the temperature is reduced from room temperature to below magnetic transition temperature, the preferentially occupied Mn majority-spin eg orbital changes from the in-plane d_x²_-y² to the out-of-plane d_3z²_-r² orbital for LZMO/STO, and vice versa for LZMO/ MgO. Experimental results suggest that the new hopping path that is mediated by the Mn²⁺ ions triggers a stronger d_3z²_-r² orbital ordering of Mn³⁺ ions and enhances the ferromagnetic coupling between the Mn spin moments of t_2g electrons in LZMO/STO, whereas the strong tensile strain stabilizes the d_x²_-y² orbital by inducing lattice distortions of the MnO₆ octahedra in LZMO/MgO. [ABSTRACT FROM AUTHOR]