Transport Behavior in Spinel Oxide MgTi2O4

Spinel oxide MgTi2O4 is synthesized by the spark plasma sintering method. The temperature dependences of magnetic susceptibility and resistance are measured and investigated in detail. It is shown that the transition of MgTi2O4 occurs at the phase transition temperature Tt - 258K. The fits of resistance versus temperature curve demonstrate that MgTi2O4 displays metal behavior above Tt, while a dual conducting mechanism, the Mort-insulator-like variable range hopping and normM activated conduction, is suggested to be responsible for the transport behavior of MgTi2O4 below Tt.