Understanding supercritical martensitic phase transformations with DFXM

The aim of this experiment is to investigate the phenomenon of supercritical martensitic phase transformations for multiferroics with exceptional reversibility and hysteretic behaviors. New research suggests that when the transformation takes place in a supercritical thermodynamic state, the material can exhibit exceptional reversibility and low hysteretic or “anhysteretic” behaviors. Based on previous X-ray diffraction studies, we hypothesize that supercritical martensitic phase transformations take place via a gradual transformation of the lattice. Our goal is to test this hypothesis by imaging the microstructure evolution as the material approaches and surpasses the critical point using in-situ dark-field X-ray microscopy during electrical biasing BaTiO3 at different temperatures. The expected outcome is a fundamental understanding of supercritical behavior in multiferroic materials, leading to the design of new multiferroics with exceptional reversibility and hysteretic properties.