Science Daily March 6, 2023
Mechanical flexibility of two-dimensional (2D) materials is shown to bring about unexpected behaviors to the recently discovered monolayer ferroelectrics, especially those displaying normal, off-plane polarization. Researchers at Rice University introduced a “ferro-flexo” coupling term into the energy expression, to account for the connection of ferroelectricity and bending of the layer, to predict and quantify its spontaneous curvature and how it affects the phase transitions. With InP as a representative example, the first-principles calculations revealed strong coupling between the ferroelectric polarization and the curvature of the layer having profound consequences for both mechanics and ferroelectricity of the material. Due to flexural relaxation, the spontaneous polarization and the transition barrier rose significantly, leading to large changes in the Curie temperature, coercive field, and domain wall width and energy, based on simulations. The polarization switching induces an overall layer bending enabling a conversion of electrical signal to movement as an actuator. They briefly discussed its possible work-cycles and maximum work-efficiency… read more. TECHNICAL ARTICLE
Abstract. Credit: ACS Nano 2023, XXXX, XXX, XXX-XXX, February 28, 2023