Evidence of very high coercive fields in orthoferrite phases of PLD grown thin films

Thin magnetic layers have been prepared by pulsed laser deposition (PLD) from targets of the orthoferrites: DyFeO3, GdFeO3 SmFeO3 and YFeO3. All layers were deposited onto quartz substrates at 450°C under oxygen partial pressures ranging from 0 to 80 mTorr. The resulting layers display evidence of various magnetic phases, including garnet and orthoferrite phases, as evidenced by X-ray diffraction. The magnetic properties of the thin films have been analysed using SQUID and vibrating sample magnetometries. A simple model is proposed to aid the analysis of hysteresis loops for samples of more than one magnetic phase. The orthoferrite phases display very high coercive fields, in the range 1.5-1.8 T.