Magnetic properties of the heavy-fermion antiferromagnet CeMg3

We have grown the single crystals of CeMg3 and its nonmagnetic analog LaMg3, which crystallize in the cubic crystal structure with the space group Fm (3) over barm, and studied their magnetic properties on well-oriented single crystals by measuring the magnetic susceptibility, magnetization, electrical resistivity, and heat capacity. CeMg3 orders antiferromagnetically with a Neel temperature T-N of 2.6 K. The specific heat capacity at low temperature exhibits an enhanced Sommerfeld coefficient of 370 mJ/K-2 mol, indicating the heavy-fermion nature of CeMg3. An estimation of the Kondo temperature T-K was made and it was found that it is of a magnitude similar to that of T-N. The reduced value of the magnetization below the ordering temperature, together with the reduced entropy at the magnetic ordering temperature and the enhanced low-temperature heat capacity, indicates that Kondo effect plays a significant role in this compound. The electrical resistivity measurement suggests that CeMg3 is a Kondo lattice compound. We have performed a crystalline electric field (CEF) analysis on the magnetic susceptibility and the heat capacity data and found that the ground state is a Gamma(7) doublet with an overall splitting of 191 K.