Influence of temperature on the avalanche dynamics of ferroelectric domain switching in barium titanate single crystals

This study investigates the avalanche dynamics of ferroelectric domain switching in barium titanate single crystals across a range of temperatures using acoustic emission techniques. Ferroelectric domain switching induced by an electric field exhibits scale-invariant avalanche dynamics, with the energy exponent increasing from 1.63 ± 0.067 at room temperature to 1.92 ± 0.045 near the Curie point, before decreasing at higher temperatures. This peak in the exponent is attributed to the interplay between equilibrium critical fluctuations and avalanche criticality. As the temperature approaches the Curie point, smaller domains and reduced polarization promote lower-energy switching, increasing the energy exponent. Near the Curie temperature, equilibrium fluctuations further modify the energy landscape, likely generating more phase boundaries and amplifying the energy exponent. Above the Curie temperature, electric field-induced phase transition dominates the switching process, where the higher energy barrier hinders switching, resulting in more energetic events and a lower energy exponent. Across all temperatures, waiting time distributions exhibit double power-law behavior, with exponents of −1 ± 0.05 for short times and −2 ± 0.10 for long times, while aftershock activity follows Omori's law with an exponent close to −1, indicating robust temporal correlations in ferroelectric domain switching. This study underscores that the avalanche dynamics of ferroelectric domain switching can be effectively modulated by temperature.