The ferroelectric phase transition in minute isometric crystals of lead titanate

Abstract

The Pm3m-P4mm phase transition and domain structure formation in isometric PbTiO₃ crystals measuring from 5 to 50μm have been investigated. The transformation is fast and involves propagation of a single {023} plane phase boundary. A size effect has been found, viz., in crystal smaller than approximately 20μm, no 90° domains occur at the phase boundary, and thermal hysteresis of the transition is by a factor of two larger, in agreement with predictions of a Landau-type phenomenological theory.

Keywords:

• Domains
• phase boundary
• phase transition
• thermal hysteresis
• size effect