Coexistence of Kondo effect and Ferromagnetism in Ce1.5Nd1.5Al

Abstract

The possibility for a coexistence of Kondo effect and ferromagnetism in Ce_1.5Nd_1.5Al has been studied using heat capacity and resistivity. The sample is of polycrystalline in nature. Heat capacity data confirms the heavy fermion behavior of this compound with a Sommerfeld coefficient γ = 190mJ/mol-K² and Debye temperature ∼ 180K. An upturn in resistivity and heat capacity observed near ∼ 24K is attributed to the paramagnetic to ferromagnetic transition as reported. Kondo like behavior is observed below 10K and vanishes for magnetic fields of the order of 2T. Around 60K a prominent jump or cusp like behaviour is seen and observed to be robust against magnetic fields up to 14T. Heat capacity below 20K is found to be consistent with equation C_p (T) = γ T + βT³ + αT^3/2e^-Δ/T that signifies the presence of a gap in magnon excitation energy of the order of 70K.