Study of Complex Magnetic Phases in LuFe2O4

We report the magnetic properties of polycrystalline LuFe2O4 sample prepared by solid state route. DC magnetization shows paramagnetic to ferrimagnetic transition at 239 K. We have observed frequency dependent real and imaginary part of ac susceptibility around 230 K i.e. just below the ferrimagnetic transition and fitted the scaling law. Fitted parameters show that the behavior is like spin glass whereas no such frequency dependence is observed for low temperature magnetic anomaly. Also frequency divergence of χ3R around 230K proves the spin glass like behavior. Temperature variation of χ2R shows that there is no change in spontaneous magnetization below ferrimagnetic transition.