Critical behavior and magnetic entropy change in La0.7Ca0.3Mn0.9Zn0.1O3 perovskite manganite

We studied the critical behavior and magnetic entropy change in a perovskite-manganite compound of La0.7Ca0.3Mn0.9Zn0.1O3 around its Curie temperature of TC = 206.75 K. Experimental results revealed that the sample exhibited the second-order magnetic phase transition with the exponents β = 0.474 and γ = 1.152 close to those expected from the mean-field theory (β = 0.5 and γ = 1.0). In the vicinity of TC, the magnetic entropy change ΔSM reached maximum values of 1.1, 1.7, and 2.7 J/kg K under magnetic-field variations of 10, 20, and 35 kOe, respectively. These ΔSM values are much lower than those reported previously on the parent compound of La0.7Ca0.3MnO3. The nature of this phenomenon is discussed by means of the characteristics of the magnetic phase transition, and critical exponents.