Quantum breathers in a nonlinear Klein Gordon lattice

Service de Recherches de Métallurgie Physique, CEA-Saclay/DEN/DMN 91191-Gif-sur-Yvette Cedex, France
Physica D Nonlinear Phenomena (Impact Factor: 1.83). 04/2006; DOI: 10.1016/j.physd.2005.12.019
Source: arXiv

ABSTRACT The quantum modes of a nonlinear Klein Gordon lattice have been computed numerically [L. Proville, Phys. Rev. B 71 (2005) 104306]. The on-site nonlinearity has been found to lead to a phonon pairing and consequently some phonon bound states. In the present paper, the time-dependent Wannier transform of these states is shown to exhibit a breather-like behavior, i.e., it is spatially localized and time-periodic. The typical time the lattice may sustain such breather states is studied as a function of the trapped energy and the intersite lattice coupling.

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