Emerging interfacial magnetization in isovalent manganite heterostructures driven by octahedral coupling

The distortion of corner-sharing octahedra in isovalent perovskite transition-metal oxide interfaces have proven to be an excellent way to tailor the electronic and magnetic properties of their heterostructures. Combining depth-dependent magnetic characterization using polarized neutron reflectivity (PNR) and theoretical calculations (density functional theory), we report interface-driven magnetic exchange interactions due to modification in the octahedral rotations at the interfaces of the isovalent ${\mathrm{La}}_{0.67}{\mathrm{Ca}}_{0.33}{\mathrm{MnO}}_{3}/{\mathrm{La}}_{0.67}{\mathrm{Sr}}_{0.33}{\mathrm{MnO}}_{3}$ heterostructures. PNR results determined a length scale of $\ensuremath{\sim}8$ unit cells at the interface, which demonstrated a modification in magnetic properties. The results also predicted a low-temperature exchange bias for these ferromagnetic heterostructures with a maximum exchange bias for the heterostructure, which showed an enhanced antiferromagnetic coupling at the interfaces.