Nickle Concentration Effect on Low Magnetic Field Magnetocaloric Properties for Ni 2+ x Mn 1− x Ge

Low magnetic field magnetocaloric properties of Ni2+xMn1−xGe near phase transition from a ferromagnetic to a paramagnetic state were investigated theoretically for level of doping x = 0.1 and 0.2. It is shown that the change of Ni content allows the magnetocaloric effect in Ni2+xMn1−xGe to be tunable, which is more practical for construction magnetocaloric refrigeration. Furthermore, the results show that the magnetocaloric properties of Ni2+xMn1−xGe samples are significantly larger and comparable with some magnetocaloric properties of many materials like La1−xCdxMnO3, Gd1−xCaxBaCo2O5.5, Ge0.95Mn0.05, La1.25Sr0.75MnCoO6, Ni58Fe26Ga28, and MnAs films.