Exploring nature of magnetic ordering and probing magnetic polaronic state near the ferromagnetic transition in EuB₆ single crystal using Magneto-optical imaging

Prior to the onset of the ferromagnetic transition in semimetal EuB₆, unusual magnetic and electric behavior have been reported in this material. Using a highly sensitive magneto-optical imaging (MOI) technique, the behavior of magnetic domains in a EuB₆ single crystal has been visualized. The transformation from a paramagnetic to a ferromagnetic state is shown to be non-Curie Weiss like and proceeds via multiple breaks in the curvature of the temperature-dependent local magnetization. From this experiments, three characteristic boundaries, T^*(H), T^*_c1(H) and T_c2(H), in a field - temperature magnetic phase diagram have been identified