Surface evolution of a stressed elastic layer in an electric field

The surface evolution of an elastic layer subjected to a far-field uniform tensile stress in an electric field is analysed by using the linear perturbation theory. The driving force controlling the surface growth is the gradient of the chemical potential associated with surface energy, elastic strain energy and electric energy, and surface diffusion is the dominant mechanism of mass transport. An analytical expression of the dispersion relation is obtained, which describes the morphological evolution of the layer in an electric field. It is found that there exists a region, in which any surface perturbation will not lead to the morphological instability of the elastic layer due to the confinement of electromechanical interaction. The electromechanical interaction can either enhance or suppress the growth of the surface perturbation.