Self-assembled growth of Sr(Ti,Fe)O3–CoFe2O4 magnetic nanocomposite thin films

Iron-substituted SrTiO3-CoFe2O4 nanocomposite thin films were grown by pulsed laser deposition on (001) SrTiO3 substrates, and their structure and magnetic properties were compared with those of single phase films. Both CoFe2O4 thin films grown in oxygen and under vacuum exhibited an in-plane magnetic easy axis, but films grown in vacuum exhibited polycrystallinity and additional metallic phases. Sr(Ti,Fe)O3 grown under high vacuum conditions showed an out-of-plane easy axis, whereas films grown in oxygen had no ferromagnetism. Nanocomposite thin films grown under high vacuum exhibited a terraced microstructure with out-of-plane easy axis. On the other hand, nanocomposites grown in oxygen exhibited two-step switching and much higher saturation magnetization. The results are consistent with dominant magnetoelastic anisotropy.