CHAOTIC BEHAVIOR IN NONLINEAR LATTICES

Forced vibrations of nonlinear lattices, consisting of one or two part icles vibrating one dimensionally, are investigated. Harmonic response , bifurcations and chaotic behaviour are considered. We use the Toda p otential, the Morse potential and a third ''combined'' potential as th e interaction potentials between the adjacent particles in the models. The third potential is obtained via a parametric combination of the T oda and Morse potentials. External loading is harmonic. The attractors , their phase portraits, the associated Lyapunov exponents and the pow er spectra are obtained and discussed. For different sets of parameter s considered, the lattice shows periodic, quasi-periodic or chaotic ch aracter. The effect of the type of the interaction potential on the be haviour of the lattice is studied. Comparative results are presented i n the form of attractor grids.