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Statistical approach of the modulational instability of the discrete self-trapping equation

Anca Visinescu·D. Grecu
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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.

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Anca Visinescu, D. Grecu. 2002-12-19. Statistical approach of the modulational instability of the discrete self-trapping equation. https://doi.org/10.1140/epjb%2Fe2003-00215-3

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