Heat capacity and magnetocaloric effect in CoS1.84Se0.16

Abstract

Abstract The first order paramagnetic (PM)-ferromagnetic (FM) transition in CoS 1.84 Se 0.16 is studied using in-field heat capacity measurement. From the low temperature C P data at zero field, the coefficient of electronic contribution to heat capacity ( γ ) and Debye temperature ( θ D ) are found to be 25 mJ/mol-K2 and 490 K, respectively. Heat capacity shows a sharp, symmetric peak at the magnetic transition ≈ 67 K in the absence of applied magnetic field and peak position shifts towards high temperature with magnetic field. The entropy of the transition is found to be ≈ 0.68 J/mol-K which is dominated by electronic contribution. In-field heat capacity measurement allowed us to estimate all the magnetocaloric (MCE) parameters relevant for magnetic refrigeration i.e. isothermal change in entropy ( - Δ S th ), adiabatic change in temperature ( Δ T ad ), relative cooling power (RCP), cooling capacity (q) etc. Temperature dependence of both - Δ S th and Δ T ad show a table-top like behaviour with almost field independent maxima above 4 Tesla.