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: 1.64). 04/2006; 216(1):191-199. DOI: 10.1016/j.physd.2005.12.019
Source: arXiv


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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Available from: Laurent Proville, Jul 15, 2014
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    • "Inspection of the spatial dependence of the various components of the n = 2 excitation operator revealed the localized nature of the excitation [40]. Proville has addressed the spatial and temporal correspondence between the classical and quantum breathers of the non-linear Klein-Gordon lattice [41], by forming a Wannier wavepacket as a linear superposition of energy eigenstates which exhibited both the localized and oscillatory nature of the quantum excitations. "
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