Two successive magnetic transitions in Y2Cu2O5 studied by μSR

Zero field muon spin rotation and magnetic susceptibility experiments on investigation of magnetic properties of cuprate Y2Cu2O5 have been performed in the temperature range 4.2-30 K. Transverse field μSR-experiments have been also carried out in order to obtain accurate information about transition temperature and to study the influence of the external magnetic field. Our data show that two magnetic phase transitions occur in Y2Cu2O5 with lowering temperature. Upper Neel temperature TN = 13 K is consistent with previous experimental data. We obtained the temperature dependence of the local magnetic field on the muon Bμ(T) in the antiferromagnetic phase. Bμ(T) reveals a peculiarity (some change of the slope) near the temperature TN = 7.5 K, which can be interpreted as an additional magnetic phase transition caused by a change in magnetic ordering of the copper subsystem. Applying a small external magnetic field 50 Oe leads to smearing of the peculiarity in Bμ(T) dependence. (orig.)