%0 Journal Article
%T Complex dielectric and impedance behavior of magnetoelectric Fe2TiO5
%A Shivani Sharma
%A Tathamay Basu
%A Aga Shahee
%A K. Singh
%A N. P. Lalla
%A E. V. Sampathkumaran
%J Physics
%D 2015
%I arXiv
%R 10.1016/j.jallcom.2015.12.090
%X We have investigated the complex dielectric and impedance properties of magnetoelectric compound Fe2TiO5 (FTO) as a function of temperature (T) and frequency (f) to understand the grain (G) and grain boundary (Gb) contributions to its dielectric response. The temperature and frequency dependent dielectric permittivity data shows a sharp increase in permittivity above 200K accompanied with a frequency dependent peak in loss. At T less than 175K, only G contribution dominates even at lower frequency (nearly 100Hz), but for T greater than 175K, the Gb contribution starts appearing at low frequency. The value of critical frequency distinguishing these two contributions increases with increasing temperature. The observed non-Debye dielectric relaxation follows thermally activated process and is attributed to polaron hopping. Further the frequency dependence of ac conductivity follows the Jonscher power-law. The temperature dependency of critical exponent s shows that the correlated barrier hopping model is appropriate to define the conductivity mechanism of FTO in the studied temperature regime.
%U http://arxiv.org/abs/1512.03889v1