Investigation of critical behavior in La1-xCexMn2Si2 (x=0.35 and 0.45) by using the dependence of magnetic entropy change

The critical exponents of La 1-x Ce x Mn 2 Si 2 (x=0.35 and 0.45) compounds are studied in the vicinity of Curie temperature (T C ), which is a second order phase transition. The magnetic field dependence of the magnetic entropy change is brought out and implemented to deduce the critical exponents. The critical exponents are estimated by various techniques such as the Modified Arrott plot and critical isotherm technique. The obtained values of critical exponents for both compounds have been satisfied with the scaling theory. The results have showed that the critical values and universal curve depends on the strength of secondary magnetic phase existing in the compound, which is antiferromagnetic phase in our case.