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Polarobreathers in soft potentials

J. Cuevas·P. G. Kevrekidis·D. J. Frantzeskakis·A. R. Bishop
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Abstract

We consider polarons in models of coupled electronic and vibrational degrees of freedom, in the presence of a soft nonlinear inter-particle potential (Morse potential). In particular, we focus on a a bound state of a polaron with a breather, a so-called ``polarobreather''. We analyze the existence of this branch based on frequency resonance conditions and illustrate its stability using Floquet spectrum techniques. Multi-site solutions of this type are also obtained both in the stationary case (two-site polarons) and in the breathing case (two-site polarobreathers). We also obtain a different branch of solutions, namely a polaronic nanopteron.

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J. Cuevas, P. G. Kevrekidis, D. J. Frantzeskakis, A. R. Bishop. 2005-12-29. Polarobreathers in soft potentials. https://doi.org/10.1103/physrevb.74.064304

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