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Radiationless Travelling Waves In Saturable Nonlinear Schrödinger Lattices

T. R. O. Melvin·A. R. Champneys·P. G. Kevrekidis·J. Cuevas
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Abstract

The longstanding problem of moving discrete solitary waves in nonlinear Schr{ö}dinger lattices is revisited. The context is photorefractive crystal lattices with saturable nonlinearity whose grand-canonical energy barrier vanishes for isolated coupling strength values. {\em Genuinely localised travelling waves} are computed as a function of the system parameters {\it for the first time}. The relevant solutions exist only for finite velocities.

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T. R. O. Melvin, A. R. Champneys, P. G. Kevrekidis, J. Cuevas. 2006-07-05. Radiationless Travelling Waves In Saturable Nonlinear Schrödinger Lattices. https://doi.org/10.1103/physrevlett.97.124101

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