SPECIFIC-HEAT MEASUREMENTS ON (ND1-XSMX)(2)CUO4 IN APPLIED MAGNETIC-FIELDS

Low-temperature specific heat measurements were performed on polycryst alline samples of (Nd1-xSmx)(2)CuO4. All samples show an anomaly at lo w temperatures characterized by a maximum in the specific heat, as pre viously reported for the pure compounds, which has been associated wit h a transition to an ordered state of the rare earth ion. The results at zero field show that there are two different mechanisms involved in the rare earth ordering process in the mixed compounds. Measurements on these samples in applied magnetic fields reveal that the temperatur e at which the maximum occurs decreases slightly with increasing field for Sm-rich samples and increases for Nd-rich samples.