Ferromagnetic and Reentrant Spin Glass Properties in an Ising Magnet Fe_xTiS₂

抄録

Magnetic measurements are made on a random ferromagnet Fe_xTiS₂ (0.36≤x≤0.43). Analysis of the magnetization curve for x=0.38 and 0.42 shows that both compounds show the behavior characteristic of an Ising ferromagnet down to 4.2 K. No sign of reentrant spin glass phase is observed in the magnetization data. Time decay of the isothermal remanent magnetization M_IR(t) is measured for x=0.37 and 0.38. The M_IR vs t curve changes from one type to another at ∼29 K for x=0.37 and at ∼21 K for x=0.38. These temperatures are tentatively assigned as the reentrant spin glass transition temperatures. Combined with our previous study, the temperature vs concentration phase diagram is determined.