Aj. Bell, On the origin of the large piezoelectric effect in morphotropic phase boundary perovskite single crystals, APPL PHYS L, 76(1), 2000, pp. 109-111
The high-field behavior of perovskite ferroelectrics close to a morphotropi
c phase boundary is investigated using the thermodynamic theory of ferroele
ctrics. For Pb(Zr0.55Ti0.45)O-3, a phase transition from the rhombohedral t
o the tetragonal state is predicted for a critical field of approximately 4
MV m(-1) parallel to the [001] axis. The transition is characterized by a
strain of 0.015 parallel to [001]. It is postulated that this transition is
the origin of the large field-induced strains observed in single crystals
of complex perovskite solid solutions with morphotropic phase boundaries. I
t is proposed that the transition is diffuse with respect to the applied fi
eld due to the inhomogeneity of the critical field arising from the B-site
disorder in the complex perovskites. A simple random-field model illustrate
s the hypothesis. (C) 2000 American Institute of Physics. [S0003-6951(00)02
501-8].