Magnetism in epitaxial PrCoO3 and Pr0.7Y0.3CoO3 thin films

Lattice distortions can stabilize magnetic ground states not observed in the bulk for thin films of undoped cobalt perovskites ACoO3. We have found that lattice distortions, in the form of tensile epitaxial strain, can stabilize a ferromagnetic ground state in PrCoO3 thin films below 65 K. However, in Pr0.7Y0.3CoO3, which has a smaller unit cell, similar levels of tensile strain are insufficient to induce ferromagnetism. These results indicate the importance of A-site cation choice for Co spin-state and Co-O-Co exchange interactions, offering another dimension to tune magnetic order in thin film cobalt perovskites.