Electronic and magnetic properties of quadruple manganite Ca$_{1-x}$Sr$_{x}$Mn$_{7}$O$_{12}$ films

We investigate the functional properties of epitaxial Ca$_{1-x}$Sr$_{x}$Mn$_{7}$O$_{12}$ films to better understand the underlying physical phenomenon in this perovskite system. We utilize oxide molecular beam epitaxy to fabricate Ca$_{1-x}$Sr$_{x}$Mn$_{7}$O$_{12}$ thin films. The epitaxial films were achieved through a two-step oxygen/ozone post-growth anneal. In parent x$=$0 films, we find bulk-like electronic and magnetic properties including an abrupt increase in resistivity at 425 K due to a nominal charge ordering transition and a net magnetization below 43 K likely arising from helical magnetic order. Finally, we will present on how tuning the Sr concentration alters the electronic and magnetic properties, providing a means to control the phase transition temperatures. The results highlight the scientific opportunities in heterostructures based on quadruple manganites.