Field-Induced Transitions Between Antiferroelectric and Ferrielectric Phases

Abstract

We have recently reported a new 3-layer field-induced ferrielectric (SmC*_{Fi1_2}) phase, which can be accessed either from the usual ferrielectric 3-layer (SmC*_Fi1) phase or as a two-stage process initially from the 4-layer (SmC*_Fi2) phase. Simple analytical models can predict the threshold fields for the field-induced transitions from: (i) 4-layer to synclinic (SmC*); (ii) 4- to SmC*_Fi1; (iii) SmC*_Fi1 to 3 SmC*_{Fi1_2}; and (iv)SmC*_{Fi1_2} to SmC*. Each of these thresholds is defined by equations involving the interlayer interaction strengths. We deduce the resulting field-temperature phase diagrams and show their agreement with experimental data.

Acknowledgments

We are grateful to the University of Manchester and the Engineering and Physical Sciences Research Council (Grant No. EP/D069793/1) for funding. AL is grateful to the Egyptian Government for a PhD Scholarship.