ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
It was reported that La3Co is an interesting superconductor which has a critical temperature Tc of 4.5 K. Pr3Co and Nd3Co are ferromagnetic materials, which have Curie temperatures of 10 and 25 K, respectively. It was claimed that their magnetic structures are associated with the canting moment reflected to the symmetry of their crystal structure. In this paper we present the results of the specific heat measurement in these compounds in the temperature range from 2 to 30 K by a standard adiabatic heat pulse method. Two phase transitions are observed at 8 and 25 K in Nd3Co. One of them at 25 K corresponds to the Curie temperature mentioned above. Another is the transition corresponds to the moment reorientation, which was observed in the thermomagnetic curves and electrical resistivity measurement. This results claim that the moments are canted in this compounds. Magnetic entropy reaches 90% of R ln 2 at 25 K. However, it increases above the Curie temperature because the crystalline electric field effects plays an important role in this compounds. There are two peaks of 10 and 12 K in Pr3Co. The above temperature corresponds the Curie temperature but another was unknown. Thus we performed the specific heat measurement for Pr7Co3, which is very close to the Pr3Co in the phase diagram. We could observe the phase transition at 12 K for Pr7Co3 in the specific heat measurement and electric resistivity measurement. It is clear that the phase transition at 12 K comes from impurity of Pr7Co3 in our Pr3Co compound. We prepare the good quality sample of Pr3Co and try to examine the specific heat measurement. © 1996 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.361964
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