Analytical study of moving excitations for one-dimensional homogeneous lattice with quartic anharmonicity

The moving nonlinear excitations (intrinsic localized vibrational modes) fo r one-dimensional homogeneous monoatomic lattice with quartic anharmonicity are obtained analytically by means of the semidiscrete approximation, with which the carrier wave is treated explicitly while the envelope function i s described in the continuum approximation. Besides the moving pulse-like t ype of excitations which was found previously in both analytical and numeri cal works, we find that the moving kink-like type of excitations can also e xist. And the kink-like excitations appeared previously only in the station ary form for such a lattice system.