Low-field magnetocaloric effect in antiperovskite Mn3Ga1−Ge C compounds

Abstract A series of Mn3Ga1−xGexC (x=0, 0.1, 0.2) compounds were prepared by solid state reaction, and their magnetic properties, phase transitions, and magnetocaloric effect were investigated. All samples, after becoming ferromagnetic below Curie temperature Tc, undergo a first-order ferromagnetic–antiferromagnetic transition at Tt at low temperature, giving rise to conventional and inverse magnetocaloric effect. Tt increases while Tc shows a decrease with the increase of Ge content. Isothermal magnetization curves around Tt are strongly history-dependent, which may result in spurious peak in the magnetic field induced entropy change ( Δ S M ). The magnetothermal properties near Tt, compared with those near Tc, are of larger Δ S M , but have larger magnetic hysteresis and smaller refrigerant capacity.