Kinetics of domain redistribution in SrTiO3 under pulsed electric fields

Abstract

SrTiO3 is a well-studied perovskite system which undergoes an antiferrodistortive phase transition at 105K. The low-temperature tetragonal phase exhibits different domains corresponding to the orientation of the symmetry axis. The domain structure can be changed drastically by applying electric fields. Using time-resolved neutron diffraction, the kinetics of the domain redistribution has been investigated on a time scale between microseconds and seconds. It is shown that there are at least two different types of relaxation processes on different time scales which govern the transformation. These can be related to the motion of hard and easy domain walls. Moreover, it is demonstrated that at low temperatures the field induced transition into the ferroelectric phase reveals a significant hysteresis which is reflected by the distribution of tetragonal domains. This finding supports the view of the zero field so-called quantum-paraelectric or coherent-paraelectric phase consisting of polar clusters which are removed only by heating above 40K.