On the possibility of mixed phases in disordered quantum paraelectrics

Abstract

We present a theory of phase transition in quantum critical paraelectrics in presence of quenched random-Tc disorder using replica trick. The effects of disorder induced locally ordered regions and their slow dynamics are included by breaking the replica symmetry at vector level. The occurrence of a mixed phase at any finite value of disorder strength is argued. A broad power law distribution of quantum critical points and and its finite temperature consequences are predicted. Results are interesting in the context of a certain class of disordered materials near quantum phase transition.