Freezing of short-range ordered antiferromagnetic clusters in the CrFeTi₂O₇system

We report on the CrFeTi₂O₇(CFTO) system using a combination of x-ray diffraction, dc magnetization, ac susceptibility, specific heat and neutron diffraction measurements. CFTO is seen to crystallize in a monoclinicP2₁/asymmetry. It shows a glassy freezing atT_f∼22 K, characterized by the observation of bifurcation between ZFC and FCχ(T) curves, frequency dispersion acrossT_fin ac susceptibility, and follows Vogel-Fulcher and power law type critical dynamics, very slow relaxation of iso-thermal remanent magnetization with time and a linear temperature dependence of magnetic contribution to specific heatC_mbelowT_f. The microscopic neutron diffraction analysis of CFTO not only confirms the absence of long-range antiferromagnetic (AFM) ordering but also exhibits diffuse scattering due to the presence of short-range ordered AFM correlated spin clusters.