Investigation of magnetization change in GdFeCo/DyFeCo exchange-coupled films

The exchange-coupled films (GdFeCo/DyFeCo) were prepared by sputtering method. The magnetization transitions caused by temperature changes had heen investigated for the films.The results indicate that the magnetization direction of the readout layer changes from in-plane to perpendicular when temperature increases.The transition occurs mainly as a result of the changes in the saturation magnetization. When the temperature increase to near the compensation temperature, the saturation magnetization and the demagnetizing energy of the GdFeCo layer decrease, With the exchange-coupled interaction,the magnetization direction of the readout layer changes.The films can be used for center aperture detection type magnetically induced super resolution.