Strain-induced nonvolatile domain switching and tunable elastic modulus in membrane by phase-field simulation
Phys. Rev. Materials 10, 014410 – Published 23 January, 2026
DOI: https://doi.org/10.1103/597g-g87y
Abstract
Ferroelectrics underpin a broad spectrum of technological applications due to their switchable ferroelectric polarization and the associated electro-mechanical responses under electrical, optical, thermal, and mechanical stimuli. Recent advances in membrane technology offer new opportunities to tune ferroelectric polarizations via mechanical strains at relatively large magnitudes and scales. However, its influence on the tunability of mechanical responses of the membrane remains underexplored. In this work, we developed a phase-field model for freestanding ferroelectric membranes with stress-free boundary conditions on top/bottom surfaces, and achieved strain-induced nonvolatile ferroelectric domain switching in the membrane. It is discovered that a tensile/compressive strain favors in-plane orthorhombic/out-of-plane tetragonal domain structures in , which are stable after the strain is removed. This results in a difference in the elastic modulus of a membrane under different domain states, i.e., a large tunability of the elastic modulus. By controlling the temperature and Sr composition of the membrane, we found that the highest elastic tunability of ∼54% can be achieved at the paraelectric-ferroelectric (tetragonal) phase boundaries due to the energy degeneracy of the two phases that facilitates the ferroelectric-to-paraelectric phase transition. Local enhancement of elastic tunability is also realized at the phase boundaries between rhombohedral, orthorhombic, and tetragonal phases in the ferroelectric states. Our work elucidates the mechanism of nonvolatile domain switching and provides a design map to achieve tunable mechanical responses in the membrane, which is key to their potential applications in sensors, actuators, and nonvolatile ferroelectric memory devices.
