Prediction of magnetocaloric effect and spontaneous magnetization in Cu-doped MnCoGe system

In the present work, the transition, magnetocaloric properties, and spontaneous magnetization in MnCo1−xCuxGe compounds were systematically studied. The maximum magnetic entropy change values of 22.4 J kg−1 K and 10.9 J kg−1 K estimated from Landau free-energy scheme under 5 T have been observed at 271 K and 260 K for x = 0.02 and x = 0.04, and the corresponding relative cooling power values are 211.1 and 231.4 J kg−1, respectively. The nature of the first-order transition for the optimized compositions has been verified using magnetic measurements, Landau coefficients, and phenomenological model. In addition, spontaneous magnetization values extracted from isothermal magnetic entropy change plots are in good agreement with those determined from Arrott plots construction, revealing the validity of this approach to estimate the spontaneous magnetization in the first-order ferromagnetic intermetallic system.