Beam fanning used to study thermal disorder and decay of polar structures in the ferroelectric relaxor Sr0.61Ba0.39Nb2O6

Abstract

A new photorefractive approach using the temperature evolution of beam fanning to study the polar structure of the ferroelectric relaxor strontium-barium-niobate (SBN) undergoing the ferroelectric-paraelectric phase transition is proposed. A strong temperature dispersion of the decay of polar structures of different sizes is observed. We compare our results with those obtained by other measurement methods to show their dependence on the size distribution of the polar structures.