Dielectric susceptibility of a ferroelectric bilayer film with surface transition layers

Using the transverse Ising model within the framework of the mean-field theory, we investigate a ferroelectric bilayer film with the surface transition layer within each constituent slab and an antiferroelectric interfacial coupling between two slabs. The combined influence of the surface transition layer and antiferroelectric interfacial coupling on the dielectric susceptibility of a bilayer film is discussed in detail. The results show that the surface transition layer plays a crucial role in dielectric susceptibility of a bilayer film.

► We study dielectric susceptibility of bilayer with surface transition layer.
► Surface transition layer in a bilayer cannot be ignored.
► Dielectric susceptibility may present two or three peaks.
► Surface transition layer pushes peak positions to lower temperature.
► Surface transition layer depresses phase transition temperature of bilayer.