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.

Intrinsic Localized Modes in Metamaterials

“…In Although Lazarides and coworkers [7] and others have shown 3-D pictures of classical breathers, but that were based on non-linear Shrodinger equation formalism. However, in the present work, we have derived a non-linear Klein-Gordon equation, where coupling or interaction between different SRR elements is also very important.…”

“…Now, let us use creation and annihilation Bosonic operators at the nth site and the above Hamiltonian (67.9) is quantized. The non-number conserving methods for four sites and an arbitrary number of particles are shown in an important work done by P [7]. However, the method which is presented above that gives a generalized idea for solving the system for arbitrary number of particles on arbitrary number of sites.…”

Search for Light-Induced Intrinsic Localized Modes: Negative Result

“…Since the ILM excitation is a purely anharmonic phenomenon, and the anharmonic interactions are rarely known and very prohibitive for large-scale simulations, there are basically no quantitative predictions of ILM properties of real crystalline materials available. At the same time, a number of authors advocated for the existence of ILMs in solids, for example in charge-transfer materials like PtCl [6], alkali halides [7][8][9], uranium salts [10], or in strongly anharmonic lattices of some ferroelectrics and related materials [11][12][13][14][15].…”

Quantum breathers in Klein-Gordon lattice: Non-periodic boundary condition approach

“…Classical breathers can also be obtained in a non-integrable Klein-Gordon system, as done numerically by well-known technique, such as spectral collocation method, which involves minimum errors in the analysis of different breather modes. 4 Due to the localization, the length scale of such excitation assumes more significance that obviously drives us to the nano domain, whose importance in the field of applied physics cannot be denied. Now, the bulk systems characterizing DBs, or classical DBs, 4 were the right tool, but when we are dealing with the systems that are very small, the laws of classical mechanics are not valid, and we have to use a different tool of study, i.e., quantum physics, and, hence, it brings us to the quantum breathers (QB).…”