Correlation between structure and properties in multiferroic La$_{0.7}$Ca$_{0.3}$MnO$_3$/BaTiO$_3$ superlattices

Superlattices composed of ferromagnetics, namely La$_{0.7}$Ca$_{0.3}$MnO$_3$ (LCMO), and ferroelectrics, namely, BaTiO$_3$(BTO) were grown on SrTiO$_3$ at 720$^o$C by pulsed laser deposition process. While the out-of-plane lattice parameters of the superlattices, as extracted from the X-ray diffraction studies, were found to be dependent on the BTO layer thickness, the in-plane lattice parameter is almost constant. The evolution of the strains, their nature, and their distribution in the samples, were examined by the conventional sin$^2psi $ method. The effects of structural variation on the physical properties, as well as the possible role of the strain on inducing the multiferroism in the superlattices, have also been discussed.