Magnetostructural transition and dielectric anomaly in novel magnetoelectric thin films

In this paper, the magnetostructural transition and dielectric anomaly of Dy modified BiFeO₃ multiferroic thin films have been reported. We note that the as-grown films at room temperature shows an irregular magnetic domain patterns, but as the temperature increases, this irregular pattern changes to a stripe-pattern at 200??C. The phase image at 300??C shows no clear magnetic domain structure as the magnetic transition occurs around 270??C indicated by Differential Thermal Analysis (DSC) curve. Upon quenching the system back to room temperature, an irregular pattern is recovered albeit with larger magnetic domains. Incidentally, a dielectric constant anomaly has been also observed in the vicinity of ferromagnetic transition temperature.