Magnetic phase transformations in erbium monocrystal

A high-purity erbium with the content of impurity elements at the level of 10-3-10-5 at.% has been obtained by the vacuum sublimation method. Temperature and field dependencies of magnetization in erbium single crystal, applied along the c axis, were measured. Above Θ1 up to Tv = 54 K, the transition from antiferromagnetic phase into ferromagnetic one is a phase transition of the first kind which is accompained by the jump of magnetization in H = Hcr field