Discrete breathers in nonlinear LiNbO3-type ferroelectrics

Abstract

Ferroelectric materials, such as lithium niobate, show interesting nonlinear hysteresis behavior that can be explained by a dynamical system analysis by using a nonlinear Klein- Gordon equation previously constructed from the Hamiltonian with Landau-Ginzburg two-well potential. In the discrete case [Phys. Rev. B 81, 064104 (2010)], the intrinsic localized modes were shown to exist above the linear modes. Nonlinearity and discreteness of domain structures in ferroelectrics slab domains arrayed in the x-direction lead to breather solutions under different values of controlling parameters, such as interaction between the domains and damping term mainly due to pinning effect. Different types of classical breather solution, namely Hamiltonian, dissipative and moving breather solutions are shown by numerical simulation with data on actual ferroelectric materials.