We present a general theory for equilibrium-modulated phases of chiral and achiral bilayer membranes and liquid crystal films. Both bulk smectics as well as freely suspended films are considered. For flexoelectric systems, continuous structural phase transitions are predicted among square-lattice, hexagonal, and distorted two-dimensional modulated phases as a function of the applied electric fi...

We develop a Landau theory for bend flexoelectricity in liquid crystals of bent-core molecules. In the nematic phase of the model, the bend flexoelectric coefficient increases as we reduce the temperature toward the nematic to polar phase transition. At this critical point, there is a second-order transition from high-temperature uniform nematic phase to low-temperature nonuniform polar phase c...

Abstract Flexoelectricity is a universal electro-mechanical coupling effect that occurs in dielectrics of all symmetric groups and becomes dominant at the micro- nano-scales. It plays an important role evaluating micro-electro-mechanical systems (MEMS) such as energy harvesters which convert vibrational to electric energy. At finer length scales, micro-inertia effects significantly contribute b...

Biological membranes are capacitors that can be charged by applying an electric field across the membrane. The charges on the capacitor exert a force on the membrane that leads to electrostriction, i.e., a thinning of the membrane. This effect is especially strong close to chain melting transitions. A consequence is voltage induced pore formation in the lipid membrane. Since the force is quadra...

The flexoelectric and electronic properties of zig-zag graphene nanoribbons are explored under mechanical bending using state the art first principles calculations. A linear dependence induced out plane polarization on applied strain gradient is found. inferior can be improved by more than two orders magnitude hydrogen fluorine functionalization (CH CF nanoribbons). large effect predicted for n...

This study presents a mathematical size-dependent model capable of investigating the dynamic behavior sandwich perforated nanobeam incorporating flexoelectricity effect. The nonlocal strain gradient elasticity theory is developed for both continuum mechanics and flexoelectricity. Closed forms equivalent geometrical variables are developed. Hamiltonian principle exploited to derive governing equ...