Multiglass properties and magnetoelectric coupling in the uniaxial anisotropic spin-cluster-glass Fe2TiO5

The compound Fe2TiO5 (FTO) is a well-known uniaxial anisotropic spin-glass insulator with two successive glassy freezing temperatures, i.e., transverse (T-TF = 9K) and longitudinal (T-LF = 55 K). In this article, we present the results of measurements of complex dielectric behavior, electric polarization as a function of temperature (T), in addition to characterization by magnetic susceptibility and heat capacity, primarily to explore magnetoelectric (ME) coupling and multiglass properties in uniaxial anisotropic spin-cluster-glass FTO. The existence of two magnetic transitions is reflected in the isothermal magnetodielectric (MD) behavior in the sense that the sign of MD is different in the T regime T < T-TF and T > T-TF. The data in addition provide evidence for the glassy dynamics of electric dipoles; interestingly, this occurs at much higher temperature (similar to 100-150 K) than T-LF, with high remnant polarization at 10 K (similar to 4000 mu C/m(2)) attributable to short-range magnetic correlations, thereby offering a route to attain ME coupling above 77 K.