Combining experiments and modeling to characterize field driven phase transformations in relaxor ferroelectric single crystals

Abstract

Field induced phase transformations in [011]C cut and poled relaxor ferroelectric single crystals can be induced by electrical or mechanical loading. Concurrent electrical and mechanical loading drives the ferroelectric rhombohedral to ferroelectric orthorhombic phase transformation at lower threshold levels than either load alone. The current experimental technique for characterization of the large field behavior including the phase transformation requires an extensive set of measurements performed under electric field cycling at different stress preloads and stress cycling at different bias electric fields repeated at multiple temperatures. Here, a mechanism based model is combined with a more limited set of experiments to obtain the same results. The model utilizes a work–energy criterion that calculates work required to induce the transformation by overcoming an energy barrier. In the relaxor single crystals, the energy barrier of phase transformations distributed over a range of field values is represented by a normal distribution of step like transformations. The results of the combined experiment/modeling approach are compared to the fully experimental approach and error is discussed.