DOMAIN-STRUCTURE IN WEAK FERROMAGNETS NEAR THE NEEL TEMPERATURE

The domain structure of YFeO3 orthoferrite in the temperature range from 10 K up to the Néel temperature TN with particular regard to the region in the neighbourhood of TN was studied. The domain width of the stripe structure as well as the collapse field of the bubble domains were determined. It was shown that in the neighbourhood of the Néel temperature the domain structure undergoes important changes. The obtained results were compared with theoretical considerations of the domain structure properties near the transition temperature. Particularly, it was shown that the domain structure in this region has a linear character. In all the investigated crystals the effect of spontaneous demagnetization near TN was observed. This effect was explained by the influence of fluctuations on the nucleation of domains. Similar effects were observed in other orthoferrites. © 1979.