Negative Thermal Expansion in Mn<sub>3</sub>Ga(Ge,Si)N Anti-Perovskite Materials

Mn3GaN has anti-perovskite structure and there exists an abnormal thermal expansion behavior in accompanying with a magnetic transition and variation of electronic transport properties. Substitution of Ga by Ge(Si) induces the change of the thermal expansion properties and the corresponding temperature range. The structure, heat capacity, magnetic and electronic transport properties of Mn3Ga(Ge,Si)N were investigated and discussed.