Structural, magnetic, magnetocaloric properties and critical behavior of La0.6Bi0.1Sr0.3-xCaxMn0.9Cu0.1O3 manganites (with x=0.1 and 0.15)

The present paper investigates the influence of Ca- doping on the structural, magnetic, magnetocaloric properties and the critical behavior of La0.6Bi0.1Sr0.3-xCaxMn0.9Cu0.1O3 specimens (with x = 0.1 and 0.15). Powder X-ray diffraction revealed the coexistence of rhombohedral (R-3c) and tetragonal (I4/mcm) phases. The temperature dependence of magnetization suggests that samples underwent a ferromagnetic-paramagnetic transition in the vicinity of the Curie temperature (TC). According to the Banerjee criterion, the magnetic phase transition is of a second-order type. The maximum of the magnetic entropy change ( - Delta SmaxM ) was found to be 3.66 J Kg-1 K-1 and 3.74 J Kg-1 K-1 for x = 0.1 and x = 0.15 respectively, under a field change of 5 T. The modified Arrott plot, the Kouvel-Fisher procedure and the critical isotherm were used to determine the critical parameters values of beta, gamma and delta. All the obtained values of the critical exponent turned out to be close to the value of the theoretical 3DIsing model. The reliability of the critical exponent was further checked through different methods, such as the Widom scaling relationship and the magnetic equation.

Automated summary

The influence of Ca-doping on the structural, magnetic, and magnetocaloric properties of La0.6Bi0.1Sr0.3-xCaxMn0.9Cu0.1O3 specimens was investigated. The magnetic phase transition was found to be of second-order type with critical exponent values close to the 3D Ising model. The reliability of the critical exponent was further confirmed through various methods.