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arXiv · cond-mat/9603187

Quantum Breathers in a Nonlinear Lattice

W. Z. Wang·J. Tinka Gammel·A. R. Bishop·M. I. Salkola
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Abstract

We study nonlinear phonon excitations in a one-dimensional quantum nonlinear lattice model using numerical exact diagonalization. We find that multi-phonon bound states exist as eigenstates which are natural counterparts of breather solutions of classical nonlinear systems. In a translationally invariant system, these quantum breather states form particle-like bands and are characterized by a finite correlation length. The dynamic structure factor has significant intensity for the breather states, with a corresponding quenching of the neighboring bands of multi-phonon extended states.

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W. Z. Wang, J. Tinka Gammel, A. R. Bishop, M. I. Salkola. 1996-03-29. Quantum Breathers in a Nonlinear Lattice. https://doi.org/10.1103/physrevlett.76.3598

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