ANISOTROPIC MAGNETIZATION AND FIELD-INDUCED EFFECTS ON CUO HIGH-QUALITY MONOCRYSTALS

Magnetization measurements were performed on high quality and well oriented single crystals of CuO in the temperature range between 4 and 300 K and with magnetic fields ranging between 5 and 100 kOe. Both temperature- and field- dependence of the magnetization was investigated permitting to obtain a complete and consistent view of the anisotropic magnetic behavior of CuO and, in details, of the features related to its magnetic transitions. For large values of the applied magnetic field large anomalous fluctuations were detected which seem to be superimposed to the normal anisotropic behavior and indicate a metastable character. Successive measurements tend to decrease this effect which can be restored by a thermal annealing.