Heisenberg like critical properties, magnetocaloric effect and scaling in lead doped NdMnO3 single crystal

Magnetic isotherms for single crystals of Nd0.7Pb0.3MnO3 have been measured around the ferromagnetic(FM) to paramagnetic(PM) transition temperature TC. Critical exponents have been obtained by modified Arrott plots and the Kouvel Fisher method. The values of exponents are consistent with those expected for 3D Heisenberg universality class. Magnetocaloric effect (MCE) has been also studied from the magnetic isotherms. Relative cooling power (RCP) is estimated as 56.725, 66.252 and 77.163 J/Kg for 1.2, 2.2 and 4.8 T fields respectively. Universal scaling behaviour in the relative change of magnetic entropy ΔSM has been observed. The rescaled magnetic entropy change curves for different applied fields are noticed to collapse onto a single curve. It has been found that the peak entropy change, ΔSM peak at TC and RCP follow a scaling power law in magnetic field H with the exponents which are reduced in comparison to their theoretically estimated value.