Ferromagnetic ordering with Heavy Femion behavior in YbPdSi

Physical properties of the ternary compound YbPdSi are investigated. The polycrystalline sample of YbPdSi has been characterized by powder X-ray diffraction, showing the orthorhombic YPdSi-type structure. Magnetization measurements reveal ferromagnetic ordering takes place at 8 K. Specific heat data are analyzed by the crystalline electric field model, which indicates that only the ground state doublet participate in the magnetic ordering. At low temperature, a heavy fermion state with the electronic specific heat coefficient γ ∼ 300 mJ / mol K 2 is suggested. The coexistence of the heavy fermion state and the ferromagnetic ordering implies that the Kondo and theta; RKKY interactions are competing in YbPdSi.