Field-induced phase transitions and giant magnetoresistance in Dy Co single crystals

Electrical resistivity and calorimetric measurements on Dy 3 Coshow that below the Neel temperature (TN=44 K) the non-collinear antiferromagnetic structure exhibits field-induced magnetic phase transitions of a first-order type along all principal axes, accompanied by a strongly anisotropic giant magnetoresistance and by a change of the Sommerfeld coefficient of the specific heat. Quantum tunnelling of the magnetization appears to be possible for T < 0.6 K.