Statistical approach of the modulational instability of the discrete self-trapping equation
arXiv:nlin/0212043 · doi:10.1140/epjb/e2003-00215-3
Abstract
The discrete self-trapping equation (DST) represents an useful model for several properties of one-dimensional nonlinear molecular crystals. The modulational instability of DST equation is discussed from a statistical point of view, considering the oscillator amplitude as a random variable. A kinetic equation for the two-point correlation function is written down, and its linear stability is studied. Both a Gaussian and a Lorentzian form for the initial unperturbed wave spectrum are discussed. Comparison with the continuum limit (NLS equation) is done.
arXiv comment10 pages