Heat Capacity of Heavy Fermion Compound CeCu₄Ga in High Magnetic Fields

Abstract

The heat capacity in the applied magnetic field up to 9 T, susceptibility and magnetization of polycrystalline CeCu4Ga are presented. Magnetic ordering was not observed down to 2 K. For temperature T < 200 K a Curie-Weiss behavior is observable giving an effective magnetic moment µ eff = 2.53 µB/f.u. The experimental value of µ eff is close to the calculated one for a free Ce 3+ ion (µ eff = 2.54 µB/f.u.), thus indicating the presence of well localized magnetic moments carried by the stable Ce 3+ ions. At low temperatures the electronic heat capacity coefficient value depends strongly on the temperature range used for the extrapolation and applied magnetic field. We observe a typical heavy fermion behavior with γ value of about 380 mJ mol −1 K −2 obtained from extrapolation to T = 0 K of the temperature range above 7 K. However, extrapolation of the lowest temperatures range yields the γ value of 3.3 J mol

Specific heat of the Ce(Cu1−xNix)4Ga alloys

“…CeCu 4 Ga has been already widely studied and it was verified that it is non‐magnetic down to 30 mK with the Kondo temperature T K = 2.4 K. The HF state is evidenced by the large value of the electronic specific heat coefficient γ = 3.3 J mol −1 K −2 . Our previous studies of the thermopower have revealed the presence of a large positive peak at 28 K that has been ascribed to the crystal electric field (CEF) effect leading to an average split of the ground state of the order of Δ = 64 K .…”