Low field magnetic properties of us

The broad peak and jumps that occur in the isofield magnetization curves of US single crystals when these are heated after first being thermally demagnetized by cooling from above T_c to low temperatures, are investigated. The jumps (two for the [110] direction, one for the [111] direction and none for the [001] direction) are correlated with the same behaviour in the initial magnetization curves and interpreted as due to the nucleation and growth of 70, 109 and 180° domains. The crystals also exhibit a high coercivity (～ 1000 Oe) and remanent magnetization of up to 92% along the [001] direction at 4 K. This enabled us to study the peak and step behaviour also by premagnetization experiments.