Influence of spin fluctuations on the magnetocaloric behavior of Gd2Co3Al9 compound

Arc melted Gd2Co3Al9 compound crystallizes in orthorhombic Y2Co3Ga9 structure type (space group Cmcm, No. 63) as single phase. The magnetization M(T), specific heat C(T) and the resistivity ρ(T) measurements reveal an antiferromagnetic transition at 9.6 K. The temperature dependence of magnetic entropy change, -ΔSM(T), calculated from the M(B) data, gives a maximum value of entropy change -ΔSMMax=6.3J/kg.K for a field change of 0-7 T in a broad temperature range of ΔT=32K above the magnetic ordering temperature. B2 dependence of magnetic field dependent magnetocaloric effect (MCE) data in the paramagnetic regime indicates the role of applied magnetic field in suppressing the spin fluctuations. The interesting observation in this compound is that the presence of spin fluctuation smears out the MCE peak at the transition temperature and drags it to higher temperatures as a broad peak.