Coexistence of Ferromagnetism and Diamagnetism in Y-Ba-Zn-O compound

In the present study, we investigate the magnetic properties of Y-Ba-Zn-O samples in which Y(2)O(3), BaCO(3) and ZnO powders were mixed at atomic ratios of Y:Ba:Zn = 1:2:3. Abnormal magnetic behavior has been seen on the M-H and M-T curves. At liquid nitrogen temperature, the samples expel the permanent magnets but no levitation is observed unlike in type II superconducting samples. The M-H curves are quite dependent on the field direction (H//ab and HaSyenab-plane). At low field regime, ferromagnetism is clearly seen but diamagnetism appears at fields higher than 1 T. We could also see some traces of Meissner-like expulsion up to 500 Oe.