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Quantum signatures of breather-breather interactions

J. Dorignac·J. C. Eilbeck·M. Salerno·A. C. Scott
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Abstract

The spectrum of the Quantum Discrete Nonlinear Schrödinger equation on a periodic 1D lattice shows some interesting detailed band structure which may be interpreted as the quantum signature of a two-breather interaction in the classical case. We show that this fine structure can be interpreted using degenerate perturbation theory.

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J. Dorignac, J. C. Eilbeck, M. Salerno, A. C. Scott. 2003-12-16. Quantum signatures of breather-breather interactions. https://doi.org/10.1103/physrevlett.93.025504

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